Ratio in maths
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The document explains how to divide a quantity into a given ratio. It defines what a ratio is as a way to compare the relative sizes of two or more quantities. It then demonstrates how to divide a total quantity by the total parts in the ratio to get the amounts for each part, using the example of dividing 560kg into a 3:4 ratio to get amounts of 240kg and 320kg. Finally, it provides examples of dividing various quantities into different ratios.
Ratio in maths
- 1. Objective Be able to divide a quantity into a given ratio
- 2. Ratio: What does this mean? A steel alloy rod is made up of 60% iron and 40% copper. So the ratio of iron to copper is 60:40. We could simplify this to give 3:2 Ratio is used to compare the sizes of two (or more) quantities. For example: a drink is made by mixing two parts orange juice with five parts water. This relationship of 2 to 5 can be written as the ratio 2:5.
- 3. Dividing a quantity in to a ratio Divide 560kg in the ratio 3:4 Total parts 1 part parts parts 3 + 4 = 7 560 ÷ 7 = 80 3 4 3 x 80 = 240kg 4 x 80 = 320kg Divide 560kg in the ratio 3:4 is 240kg:320kg
- 4. Time to try some! 1) £900 into the ratio 4:5 2) £200 into the ratio 3:5 3) £630 into the ratio 7:11 4) 2205kg into the ratio 8:13 5) 450 hours into the ratio 5:6:7 6) 550 lbs into the ratio 5:8:9 £400 : £500 £75 : £125 £245 : £385 840kg : 1365kg 125h : 150h : 175h 125lbs : 200lbs : 225lbs