Class 5th(maths) how many squares ppt
- 1. KENDRIYA VIDYALAYA, IIT . CHENNAI-36
- 3. • A rectangle is a 2-D shape With four sides and four right angles (90 ̊) • The opposite sides of rectangle are equal and parallel • It has different length and breadth.
- 4. 8 cm 8 cm 4 cm 4 cm
- 9. Area • Area is the amount of space inside the boundary of a flat surface. • All the sides of this square are 1 cm long- • What would be the area of this square? • Formula of area of square is = side x side • So the area of this square would be = 1cm x 1cm = 1 square cm or 1cm² Area 1cm1cm 1cm 1cm
- 10. • So the area of such two squares would be 2cm² • And the area of such 4 squares would be 4 cm² Area AreaArea Area AreaArea
- 11. 2 3 4 5 6 7 1
- 12. Perimeter • Length of the boundary or the distance around the outside edge of a flat surface is called perimeter. • The sides of the given square are 1 cm long • So its perimeter or boundary is = 1cm +1cm +1cm +1cm= 4cm • Formula of perimeter of square= 4xSide Area 1cm1cm 1cm 1cm
- 13. 2 3 4 5 6 7 1
- 14. 2cm 6cm 6cm The boundary or perimeter of rectangle 1 is- 2cm+6cm+2cm+6cm=16cm 2cm 4cm 4cm 3cm 3cm The number of squares in both the rectangles is same-12. So the area of both of these would be same-12 cm² But the perimeter would be different as given below
- 15. The perimeter of the rectangle-4 would be the longest 12cm 12cm 1cm 1cm Perimeter of rectangle-4 is = 12cm+1cm+12cm+1cm = 26cm
- 17. The area of different stamps Stamp Number of squares cover Area A 18 18 Square cm. B 8 8 Square cm. C 6 6 Square cm. D 12 12 Square cm. E 4 4 Square cm. F 12 12 Square cm.
- 18. Write the area (in square cm) of the shapes below
- 19. What is the area of this shape? It covers 20 squares so the area is 20 square cm. What is the area of green part? Yellow and green parts cover 20 squares so the area of yellow and green parts altogether is 20 square cm. But the green part is the half part of whole rectangle so its area will be ½ of 20= 10 square cm. Shape A Shape B Area of shape A and B
- 20. Shape F Shape F covers four squares that are more than half- filled, four squares that are less than half-filled, and four complete squares. Area of figure F = area of four squares more than half- filled squares + area of four complete squares = (4 + 4) square cm = 8 square cm What is the area of this shape? Area of shape F
- 21. Shape c Shape C covers two complete squares, two squares that are more than half-filled, and two squares that are less than half-filled. Area of figure C = area of two complete squares + area of two squares more than half-filled = (2 + 2) square cm = 4 square cm What is the area of this shape? Area of shape C
- 22. Area of shape E and D Shape E covers 18 complete squares and 6 half squares. 6half squares= 3 complete squares SO its area= 18+3=21 square cm. ⅟2 1 7 5432 10 11 12 ⅟2 6 9 17 18 ⅟215 8 1613 14 ⅟2 ⅟2 ⅟2 Shape E Shape D 1 2 4 53⅟2 ⅟2 Shape D covers 5 complete squares and 2 half squares. 2half squares= 1 complete squares SO its area= 5+1=6 square cm.
- 23. We can find out the area of a rectangle without the grid. Length=8cm Width=4cm Formula of Area of Rectangle = length x breadth So the area of this rectangle= 8cmx4cm= 32 cm²
- 24. Area of blue Triangle Blue triangle is the half part of Big rectangle. The area of big rectangle= 5cm x 4cm= 20 cm² So the area of blue triangle would be half of the area of Big rectangle= 20/2= 10 cm²
- 25. Area of Red Triangle •In Red triangle there are two halves of two different Rectangles •(Red triangle=half part of orange rectangle + half part of green rectangle) Area of Orange rectangle= 12 cm² and half of this = 6 cm² Area of green rectangle= 8 cm² and half of this = 4 cm² So the area of Red triangle = 6 cm²+ 4 cm²= 10 cm² 6 cm² 4 cm²
- 26. Here is a rectangle of area 20 square cm. (a) Draw one straight line in this rectangle to divide it into two equal triangles. What is the area of each of the triangles? (b) Draw one straight line in this rectangle to divide it into two equal rectangles. What is the area of each of the smaller rectangles? (c) Draw two straight lines in this rectangle to divide it into one rectangle and two equal triangles. • What is the area of the rectangle? • What is the area of each of the triangles?
- 27. (a) The given rectangle is divided into two equal triangles by drawing a line as shown below. Area of rectangle = 20 square cm Area of each triangle =12of area of rectangle = (20 ÷ 2) square cm = 10 square cm
- 28. (b) The given rectangle is divided into two equal rectangles by drawing a line as shown below. Area of rectangle = 20 square cm Thus, area of each small rectangle =12of area of rectangle = (20 ÷ 2) square cm = 10 square cm
- 29. (c) The given rectangle is divided into one rectangle and two equal triangles by drawing 2 lines as shown below. in the red shaded region, we have 2 completely filled squares and 2 squares that are more than half-filled. Thus, the area of red triangle = 4 square cm Similarly, the area of green triangle = 4 square cm Now, the area of remaining portion i.e. the rectangle contains 12 completely filled squares. • Thus, the area of rectangle = 12 square cm. • Area of each of the triangle is 4 square cm.
- 30. Puzzles with Five Squares Measure the side of a small square on the squared paper on page 45. Make as many shapes as possible using 5 such squares. Three are drawn for you.
- 31. Thank you