2 roundingnumericals

Indian Standard
RULES FOR ROUNDING
NUMERICAL VALUES
( Revised)
IS : 2 - X960
( Rcaflimcd 1590)
OFF
Thirteenth Reprint MAY 1992
UDC 511.135.6
@ CopVright 1960
BUREAU OF INDIAN STANDARDS
MANAK BHAVAN, 9 BAHADUR SHAH WA& MARG
NEW DELHI llOCMI2
Gr3 September 1960

IS:2- 1960
Indian Standard
RULES FOR ROUNDING OFF
NUMERICAL TSALUES
( Revised )
Engineering Standards Sectional Committkej EDC 1
Chairman
DR K. S. KRISHNAN Council of Scientific & Industrial Research,
New Delhi
Members
SHRI PREMP RAKASHI Alkrnate to
Dr K. S. Krishnan‘
ASSISTANT DIRECTOR
SHRI BALESHWARN ATH
DEPUTY DIRECTOR GENERAL OF
OBSERVATORIES
DIRECTOR
SHRI S. B. JOSHI
SHRI R. N. KAPUR
DR R. S. KRISIINAN
SHRI S. R. ME%IRA
Research, Design & Standardization Organization
( Ministry of Railways )
Central Board of Irrigation & Power, New Delhi
Directorate General of Observatories ( Ministry of
Transport & Communications ), New Delhi
Engineering Research Department, Government of
Andhra Pradesh
Institution of Engineers ( India); Calcutta
Indian Engineering Association, Calcutta
Indian Institute of Science, Bangalore
Council of Scientific & Industrial Research,
New Delhi
SHRI S. N. MUI~ERJI Government Test House, Cnlcutta
SWRI K. D. BHATTACHARJE(E A lternate )
DR B. R. NIJHA~AN Council of Scientific & Industrial Research,
New Delhi
SHRI V. R. RAGHAVAN Central Water & Power Commission, New Delhi
BRIG J. R. SAMSON Controller of Development (Armaments ) ( Ministry
of Defence )
LT-COL R. JANARDHANAM( A lterm& )
( Continued on page 2 )
MANAK BHAVAN. 9 BAHADUR SHAH ZAPAR MARG
NEW DELHI 110002

rs:2-1960
Mmbcrs
S&iRI R. N. SARUA Directorate Gcnrral of Supplies & Disposals
( Ministry of Works, Housing & Supply )
SHRI J. M. SIRHA Engineering Association of India, Calcutta
SHRI J. M. T~EEI,~N Ministry of Transport & Communications ( Roads
SHRI T. N. BHARGAVA( .lftenzate )
Wi;lg )
LT-GEN H.~%LLIA~WS Council of Scientific & Industrial Research,
New Delhi
DR LAL C. VERMAN ( Ex-oQcio ) Director, IS1
SFIRI J. P. MEliROTR.4 Deputy Director ( Engg ), IS1
( AltematG )
Secrete&s
DR A. K. GUPTA Assistant Director ( Stat ), IS1
SHRI B. N. SINGH Extra Assistant Director ( Stat ), IS1

Indian Standard
RULES FOR ROUNDING
NUMERICAL VALUES
ISr2-1960
OFF
( Revised)
0. FOREWORD
0.1 This Indian Standard ( Revised ) was adopted by the Indian Standards
Institution on 27 July 1960, after the draft finalized by the Engineering
Standards Sectional Committee had been approved by the Engineering
Division Council.
0.2 To round off a value is to retain a certain number of figures, cowted
,from the left, and drop the others so as to give a more rational form to the
value. As the Ault of a test or of a calculation is generally rounded off
for the purpose of reporting or for drafting specifications, it is necessary to
prescribe rules for ‘ rounding off ’ numerical values as also for deciding on
‘ the number of figures ’ to be retained.
0.3 This standard was origiually issued in 1949 with a view to promoting
the adoption of a uniform procedure in rounding 08 numerical values.
However, the rules given referred only to unit fineness of rounding ( see 2.3 )
and in course of years the need was felt to prescribe rules for rounding
off numerical values to fineness of rounding ‘other than unity. Moreover,
it was also felt that the discussion ‘on the number of figures to be retained as
given in the earlier version required further elucidation. The present revision
is expected to fulfil’these needs.
0.4 In preparing this standard? refcrcnce has been made?0 the following:
IS : 787-1956 GUIDE FOR INTER-CONVERSIOON F VALUES FROMO NE
SYSTEMO F UNITST O ANOTHER. Indian Standards Institution.
B.S. 1957 : 1953 PRESENTATIOONF NUMERICAVLA LUES( PIN=NESSO F
EXPRESSIONR;O UNDINQO F NUMBERS). British Standards Insti-tution.
AME&CAN -STANDARD I, 25.1-1940 RULES FOR ROUNDING OFF
NUUERICALV ALUES. American Standards Association.
ASTM DESIGNATIO: NE 29-50 RECOMMENDEPDR ACTICEF OR DESK+
NATMG SIONIFICANTP LACESI N SPECIFIEDV ALUES. American
Society for Testing and Materials.
JAU~ W. SCARBOROUGHN. umerical Mathematical Analysis., Baiti-more.
The John Hopkins Press, 1955.
3

3s : 2 - 1960
1. SCOPE
1.1 This standard prescribes rules for rounding off numerical values for the
purpose of-reporting results of a test, an analysis, a measurement or a cal-culation,
and thus assisting in drafting specifications. It also makes recom-mendations
as to the number of figures that should be retained in course
of computation.
2. TERMINOLOGY
2.0 For the purpose of this standard: the i”.4lowing definitions shall apply.
2.1 Number of Decimal Places -. A value is said to have as many
decimal placesas there are number of figures in the value, counting from the
first figure after the decimal point and ending with the last figure on the right.
Examples:
Value Decimal Places
0,029 50 5
21.029 5 4
2 ooo$Oo 001
29 1.00 2”
10.32 x lo8 2
( see Note 1 )
NOTE I- For the purpose of tliis standard, the expression 10.32 x 10s should be
taken to consist of two parts, the value proper which is 10~32 and the unit of expression
for the value, 10%
2.2 Number of Significant Figures - A value is said to have as many
number of significant digits ( see Note 2 )
left-most non-zero digit and ending with the
significant figures ai there are
in the value, counting from the
right-most digit in the value.
Examples :
Value
o-029 500
0.029 5
10.029 5
2 ooo*ooo 001
5 677.0
567 700
SigniJcani Figures
5
:
10
5
6
56.77 x lo2 4
0 056.770
3 900 I
( see Note 3 )
NOTE 2 - Any of the digits, 1, 2. 3 ,..,.. . . . . . . . 9 occurdng in a value shall be a signi-ficant
digit(s); and zero shall be a significant digit cnly when it is preceded by some

other digit (excepting
the magnitude of the
digit.
IS : 2 - 1960
zcras ) on its left. When appearing in the pow“’ of 10 to indicatr
unit in the expression of a value, zero shall not b, a signiIicant
NOTE 3 - With a view to removing anv ambiguity regarding the signilrcancr, of the
zeros at the end in a value like 3 900, it would be always desitablr to writ,, thy value in
the power-of-ten notation. For cuamplr, 3 900 may br written as 3.9 % ICI*, 3.90 x 103
or 3.900 X 103 depending upon the last figure(s) in the value to which it is drsirrd to
impart significance.
2.3 Fineness of Rounding-The unit to which a value is rounded off.
For example, a value may be rounded to the nearest O*OOO( )I, O*OOO2 ,
O*OOO 5, 0.001, 0.002 5, 0.005, O-01, 0.07, 1, 2.5, 10, 20, 50, 100 or any
other unit depending on the fineness desired.
3. RULES FOR ROUNDING
3.0 The rule usually followed in rounding off a value to unit fincness of
rounding is to keep unchanged the last figure retained when the figure next
beyond is less than 5 and to increase by 1 the last figure retained when t!rc
figure next beyond is more than 5. There is diversity of practice when the
figure next beyond the last figure retained is 5. In such cases, some com-puters
’ round up ‘, that is, increase by 1, the last figure retained; others
’ round down ‘, that is, discard everything beyond the last figure retains-d.
Obviously, if the retained value is always ‘ rounded up ’ or always ‘ mund-ed
down ‘, the sum and the average of a series of values so rounded will
be larger or smaller than the corresponding sum or average of the unround-ed
values. However, if rounding off is carried out in accordance with the
rules stated in 3.1 in one step (gee 3.3 ), the sum and the average of the
rounded values would be more nearly correct than in the previous cases
( see Appendix A .) .
3.1 Rounding Off to Unit Fineness - In case the fineness of rounding is
unity in the last place retained, the following rules shall be followed:
Rule I- When the figure next beyond the last figure or place to
be retained is less than 5, the figure in the last place retained shall be
left unchanged.
Rule II--When the figure next beyond the last figure or place
to be retained is more than 5 or is 5 followed by any figures other
than zeros, the figure in the last place retained shall hc increased
by 1.
Rule III --. When the figure next beyond the last figure or place
to be retained is 5 alone or 5 followed by zeros only, the figure in the
last place retained shall be (a) increased by 1 if it is odd and (b) left
unchanged if even ( zero would be regarded as an even number for
this purpose ).
5

IS:Z-1960
Some examples illustrating the application of Rules I to III are given
in Table I.
TABLE I EXAMPLES OF ROUNDING OFF V.UJJES TO UNIT FINENESS
VALUE FINENESSO F ROUNDING
r ~_-..__*-- ,
1 0.1 0.01 oxw1
r-- h---y c_A-._ r-_.h____y __‘h___
Rounded Rule Rounded Rule Rounded Rule Rounded Rule
Value Value Value Value
7.260 4 7 I 7.3 II 7.26 I 7.260 I
14.725 15 II 14.7 I 14.72 III(b) 14.725 -
3.455 3 I 3.5 II 3.46 III(a) 3.455 -
13.545 001 14 II 13.5 I 13.55 II 13.545 I
a.725 9 II 8.7 I a.72 III(b) a.725 -
19.205 19 I 19.2 I 19.20 III(b) 19.205 -
0.549 9 1 II 0.5 I 0.55 II 0.550 II
0.650 1 1 II 0.7 II 0.65 I 0.650 I
0.049 50 0 I 0.0 I 0.05 II 0.050 III(a)
3.1.1 The rules for rounding laid down in 3.1 may be extended to apply
when the fineness of rounding is O-10, 10, 100, 1 000, etc. For example,
2.43 when rounded to fineness 0.10 becomes 2.40. Similarly, 712 and 715
when rounded to the fineness 10 become 710 and 720 respectively.
3.2 Rornding Off to Fineness Other than Unity - In case the fineness
of rounding is not unity, but, say, it is n, the given value shall be rounded
off according to the following rule:
Rule IV- When rounding to a fineness n, other than unity, the
given value shall be divided by n. The quotient shall be rounded off to
the nearest whole number in accordance with the rules laid down
in 3.1 for unit fineness of rounding. The number so obtained, that
k, the rounded quotient, shall then be multiplied by n to get the final
rounded value,
Some examples illustrating the application of Rule IV are given in
Table II.
Nope 4 -The rules for rounding off a value to any fineness of rounding, n, may also
bc stated in line with those for unit fineness of rounding (see 3.1 ) as follows:
Divide the given value by n SO that an integral quotient and a remainder are
obtained. Round off the value in the following manner:
a) If the remainder is less than n/2, the value shall be rounded down such that
the rounded value is an integral multiple of n.
6

TABLE II EXAMPLES OF ROUNDING OFF VALUES TO FINENESS
OTHER THAN UNIT
VALUE
(0
1.647 8
2.70
2.496 8
1.75
0.687 2 1
0.875
325
1 025
FIP~BNESOSF
ROUNDING, n
(2)
0.2
0.2
0.3
0.5
@O7
0.07
50
50
QUOTIE~~T
(3)-(l)/(2)
8.239
13.5
3.322 7
3.5
9.c17 3
12.5
6.5
20.5
10
!2
G
20
3.2.1 Fineness of roundin,g other than 2 and .5 is seldom rallccl for in
practice. For‘thcse casts, the rules for rounding may 1~ st:~tccl ill
simpler form as follows:
a) Rounding off to fineness 50, 5, 0.5, O-05, 0.005, etc.
Rule, V - When rounding to 5 units, the given value shall IX
doubled and rounded elf to twice the rcq~rirc~tl fincncss of rountling in
accordance with 3.1.1. The value thus obtained shall 1~ l~alvctl to
get the final rounded value.
For example, in rounding off 975 to the nearest 50, 975 is douljlcd
giving 1 950 which becomes 2 000 when rounded off to the nearest 100; when
2 000 is divided by 2, the resulting number 1 000 is the rounded value of
975.
b) Rounding off to fineness 20, 2, 0.2, 0.02, 0.002, etc.
Rule VI- When rounding to 2 units, the given value shall be
halved and rounded off to half the required fineness of rounding in
accordance with 3.1. The value thus obtained shall then be doubled
to get the final rounded value.
For example, in rounding off 2.70 to the nearest 0.2, 2.70 is halved
giving 1.35 which becomes 1.4 when rounded off to the nearest O-1; when
1.4 is doubled, the resulting number 2.8 is the rounded value.
7

IS: 2 - 1960
3.3 Successive Rounding - The fin:11 rounded value shall be obtained
&on! the mcst prccisc v:~luc available in one step only. and not from a series
of succcssivc rouiitlings. For cxamplc, the vallre O-5.1-9 9, when rounded to
one sign&cant ligurcx, shall hc written as 0.5 and not as 0.6 which is obtained
aq a r.c.sult of auc,ccssive rolmdillgs to 0*5X’), 0.55, and O-6. It is obvious that
tit? most i)t.c.cisc value available is nearer to 0.5 and not to 0.6 and that
ti c error involved is l~,ss in the formc>l, cast‘. Similarly, 0.650 1 shall be
rr:u(ltlcd 011‘ to 0.7 in one step and not succcssivcly to 0.650, 0.65 and 0.6,
S~IICCt‘ he ~nost precise valur available here is nearer to 0.7 than to 0%
( .il i illSO ?‘d)lC 1 ).
LOTE 5 - In those casts where a linal rounded value terminates with 5 and it is
intended to use it in further computation, it may be hrlpM to use a ‘+’ or ‘-’ sign after
the final 5 to indicate whether a subsequent rounding should be up or down. Thus
3.214 7 may be written as 3-215- when rounded to a fineness of rounding 0.001. If
fur&r rourtding to three significant figures is dnlred, this number would be rounded
down and britten as 3.21 which is in error by less than half a unit in the last place;
otherwise, roundingof 3.215 would have yielded 922 which is in error by more than half
a unit in the last place. Similarly, 3.205 4 could be written as 3205+ when rounded
to 4 significant figures. Further rounding to 3 significant figures would yield the
value as 3-2 1.
In case the fina 5 is obtained exactly, it would be indicated by leaving the 5 as such
without using ‘+’ or ‘-’ sign.
In subsequent rounding the 5 would then be treated in
accordance with Mule III.
4. NUMBER OF FIGURES TO BE RETAINED
4.0 Pertinent to the application of the rules for rounding off is the under-lying
decision as to the number of figures that should be retained in a given
problem. The original values requirin g to be rounded off may arise as a
result of a test, an analysis or a measurement, in other w.ords, experimental
results, dr they may arise from computations involving several steps.
4.1 Experimental Results - Thq number of figures to be retained in an
experimental result, either for the purpose of reporting or for guiding the
formulation of specifications will depend on the significance of the figures
in the value. This aspect has been discussed in detail under 4 of IS : 787-
1956 to which reference may be made for obtaining helpful guidance.
4.2 Conlputatiions - In computations involving values of different
accuracies, the problem as to how many figures should be retained at various
s’teps assumes a special significance as it would affect the accuracy of the
final result. The rounding off error will, in fact, be injected into computation
every time an arithmetical operation is performed. It is, therefore, necessary
to carry out the computation in such a manner as would obtain accurate
results consistent with the accuracy of the data in hand.
4.2.1 While it is not possible to prescribe details which may be followed
in computations of various types, certain basic rules may be recommended
8

IS:2~1960
for single arithmetical operations which, when followed, will save labour
and at the same time enable accuracy of original data to be normally
maintained in the final answers.
4.2.2 As a guide to thyiumber of places or figures to be retained in the
calculations involving arithmetical operations with rounded or approximate
values, the following procedures are recommended:
a)
b)
c>
4
Addition - The more accurate values shall be rounded off SO as to
retain one more place than the last significant figure in the least
accurate value. The resulting sum shall then be rounded off to
the last significant place in the least accurate value.
Subtraction - The more accurate value ( of the two given values )
shall be rounded off, before subtraction, to the same @ace as the
last significant figure in &s-accurate value; and the result shall be
reported as such ( see also Note 6 ).
Multifilication and Dirrisioil- The number of sigmjicant figures
retained in the more accurate values shall be kept one more than
that in the least accurate value. The result shall then be rounded
off to the same number of significant figures as in the least accurate
value.
When a long computation is carried out jn several steps, the inter-mediate
results shall be properly rounded at the end of e&h step
so as to avoid the accumulation of rounding errors in such cases.
It is recommended that, at the end of each step, one more signi-ficant
figure may be retained than is required under (a), (b) and
(c) ( see nlso Note 7 ).
Noln 6 -The loss of the significant figures in the subtraction of two nearly equal
values is the, greatest so‘trcc of inaccuracy in most computations, and it forms the
weakest link ~1 a chain computation where it occurs. Thus, if the values 0.169 52 and
0.168 71 arc cnch cor~ct to five significant figures, their difference 0.000 81, which has
only two signifcant figures. is quite likely to introduce inaccuracy in subsequent
computation.
If, however, the tlifferencr of two ~alucs is desired to be correct to k significant figures
and if it is known brforehand that the first m significant figures at the left will disappear
by subtraction, then the number of significant figures to he retained in each of the
values shall br m $ k- (SEC &ample 1).
SOW 7 -To ensure a greater degree of accuracy in the computations, it is also
desirable to avoid or defef . s long as possible certain approximation operations like
that of the division or square root. For example, in the determination of sucrose by
voiu x lctrlc. method, the expression 12~%‘s ($A) may be better evaluated by taking
its calculational form as 20~1 !fs cl -fi VI )/wa 271 ~32 which would defer the division
until the.last operation of the calculation.
9

fS:2-1960
4.2.3 Examples
Example 1 /
Required to find the sum of the rounded off values 461.32, 381.6,
76.854 and 4.746~2.
Since the least accurate value 381.6 is known only to the first decimal
place, all other values shall he rounded off to one more place,
that is, to two decimal places and then added as shown below:
461.32
381.6
76.8.5
4.75
924.52
The resulting sum shall then be reported to the same decimal place
as in the least accurate value, that is, as 924.5.
Examjle 2
Required to ftnd the sum of the values 28 490, 894, 657.32, 39 500
and 76 939, assuming that the value 39 500 is known to the
nearest hundred only.
Since one of the values is known only to the nearest hundred, the
other values shall be rounded off to the nearest ten and then
added as shown below:
2 849 x 10
89 x 10
66 x 10
3 950 x.10
7694 x 10
14648 x 10
The sum shall then +e reported to the neakest hundred as
1 465 x 100 or even as 1,465 x 106.
Example 3
Required to find the ditTeren;e’hf 679.8 and 76.365, assuming that
each number is known to its last figure but no farther.
10

IS : 2 - 1960
since OJlC oi’ the valrws is known to the first decimal phKe only, the
other value shall also be rounded off to the first decimal place
and then the difference shah be found.
679.8
76.4
---
603.4
‘I’he diff‘crence, 603*4, shall be reported as such.
Example 4
Required to evaluate dm - t/2- cprrect to live significant
figures.
Since l/552 = 1-587 450 79
l/F s = l-577 973 38
and three significant figures at the left will disappear on sub-traction,
the number of si
nificant figures retained in each value
B
shall be 8 as shown below.
I.587 450 0
1.577 973 4
----.-
0*009 477 4
‘I’he result, WOO9 477 4, shall be reported as such‘ ( or as
9.4774 >( 10-3).
Example 5
Required to evaluate 35*2/1/z given that the numerator is correct
to its last figure.
Since the numerator here is corre$to three significant figures, the
denominator shall be taken as t/r-t 1,414. Then,
35.2
mJ I 24.89
and the resuit shall be reported as 24.9.
Example 6
Required to evaluate 3*78x/5*6, assuming that the denominator is
true to only two significant figures.
Since the denominator here is aorrrect to two significant figures, each
number in the numerator would be taken up. to three significant
11

IS:2-1960
figures. Thus,
3.78 x 3.14 = 2,08
5.7
.
The result shall, however, be reported as 2-l.
APPENDIX A
( Clause 3.0 )
VALIDITY OF RULES
A-l. Thl validity of the rules for rounding off numerical values, as given
in 3.1, may be seen from the fact that to every number that is to be ‘ rounded
down ’ in accordance with Rule I, there corresponds a number that is to
be.’ rounded up ’ in accordance with Rule II. Thus, these two rules estab-lish
a balance between rounding ’ down ’ and ‘ up ’ for all numbers other
than those that fpll exactly midway between two alternatives. In the latter
case, since the fi
ag
urg’ to be dropped is exactly 5, Rule III, which specifies that
the value shoul) be rounded to its nearest even number, implies that rounding
shall be ‘ up ’ when the preceding figures are 1,3, 5, 7, 9 and ‘ down ’ when
they are 0, 2, 4, 6, 8. Rule III hence advocates a similar balance between
rounding ‘ up ’ and ‘ down ’ ( see also Note 8 ). This ipplies that if the above
rules are followed in a large group of values in which random distribution of
figures occurs, the number ‘ rounded up ’ and the nuniber ‘ rounded down ’
will be nearly equal. Therefore, the sum and the average of the rounded
values will be more nearly correct than would be the case if all were rounded
in the same direction, that is, either all ‘ up ’ or all ‘ down ‘.
NOTE 8 - From purely logical considerations, a given value could have as well been
rounded to an odd number ( and not an even number as in Rule III ) when the discard-ed
figures fall exactly midway between two alternatives. But there is a practical
aspect to the matter. The rounding off a value to an even number facilitates the
division of the rounded value by 2 and the result!of such division gives rhe correct
rounding of half the original unrounded value. Besides, the ( rounded ) even values may
generally be exactly divisible by many more numbers, even as well as odd, than are the
( rounded ) odd values.
12

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AMENDMENT NO. 1 FEBRUARY 1997
TO
IS 2 : 1960 RULES FOR ROUNDING OFF
NUMERICAL VALUES
( Revived)
(Puge 3, clause 0.4 ) - Insert the following after first entry:
IS 1890 ( PARTO) : 1995/ISQ 31-O : 1992 QUANTITIES AND UNITS : PART 0
GENERAL PRINCIPLE ( FIRST REVISZON )
(Page 8, clause 3.3 ) - Insert the following new clause after 3.3:
“3.4 The rules given in 3.1, 3.2 and 3.3 should be used only if no specific
criteria for the selection of the rounded number have to be taken into account. In
cases, where specitir limit (‘Maximum’ or ‘Minimum’) has been stipulated or
where specifically mentioned in the requirement, it may be advisable always to
round in one direction.
Examples:
The requirement of leakage current for domestic electrical appliances
is 210 (LA (rms) maximum.
The rounding may be done in one direction. For example, if a test result
is obtained as 210.1, it will be rounded up and reported as 211 pA.
The requirement for cyanide (as CN) for drinking water is specified as
0.05 mg’l, maximum beyond which drinking water shall be considered
toxic.
is obtained as 0.051 mg/l, it will be rounded up and reported as
0.06 mg/I.
The requirement for minimum thickness of the body of LPG cylinder is
2.4 mm.
is obtained as 2.39 mm, it will be rounded down and reported as 2.3
mm.

Amend No. 1 to I§ 2 : 1960
4) The requirement for Impact-Absorption for Protective Helmets for
Motorcycle Riders is:
‘The conditioned helmet tested shall meet the requirements, when
the resultant acceleration (RMS value of acceleration measured
along three directions) measured at the centre of grfvity of the
headform shall be 5 150 gn (where gn = 9.81 m/set ) for any 5
milliseconds continuously and at no time exceeds 300 g,.’
The rounding may be done in one direction. If a test result is obtained as
150.1 gn, it will be rounded up and reported as 151 gn.”
(MSDl)
Reprography Unit, BIS, N& Delhi, India

IS 2 : 1960 RULES FOR ROUNl)lNG~OFF
NUMERtCAL VALUES
:( MSD I j

AMENDMENT N-O. 3 AUGUST 2008
TO
IS 2 : 1960 RULES FOR ROUNDING OFF
NUMERICAL VALUES
(Revised)
( Page 5, clause 3.1, para 1 ) - Substitute the first sekence for the
following:
‘In case the fineness of rounding is unity in the last place retained, the following
rules (except in 3.4) shall be followed:’
( Amenhaent No. 1, February 1997, clause 3.4 ) - Substitute the second ‘_
sentence for the following:
‘In all cases, where safety requirements or&scribed limits have to be respected,
rounding off should be done in one direction only.’
( AmendmemNo. 1, Febrrrory 1997, clause 3.4 ) - Delete ail the examples
given under this clause.
(Amendment No. 2, October 1997 ) - Delete this amendment.
(MSD3)
Reprography Unit, BiS, New Delhi, India

2 roundingnumericals

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