Page 98 - ICSE Math 6

When a mass of one kilogram is divided into thousand equal parts, then each part is called a gram.
We can use decimal system to represent a combination of any two units of weight together.
For example: (a) 2 kg and 900 g = 2.9 kg

(b) 15 kg and 55 g = 15.055 kg
(c) 8 g = 0.008 kg

Example 11: Add and express the answers in centimetres.

(a) 6 m + 17.5 m (b) 275 m + 0.66 m

Solution: (a) 06.0 (Converting to (b) 275.00 (Converting to
+ 17.5 like decimals) + 000.66 like decimals)

23.5 275.66

So, 6 m + 17.5 m = 23.5 m So, 275 m + 0.66 m = 275.66 m
We know that, 1 m = 100 cm We know that, 1 m = 100 cm
∴ 23.5 m = (23.5 × 100) cm ∴ 275.66 m = (275.66 × 100) cm
= 2,350 cm = 27,566 cm

Example 12: Express in rupees.

(a) 6 p (b) 19 p (c) 768 p (d) 675 p

 19 
Solution: (a) We know that, 1 rupee = 100 paise (b) 19 p = `  = ` 0.19
 100 
 6 
∴ 6 p = `  = ` 0.06
 100 

 768   675 
(c) 768 p = `  = ` 7.68 (d) 675 p = `  = ` 6.75
 100   100 

Word Problems

Example 13: Rahul covered 15.75 km by bus and 2.5 km by walking. What distance did he cover in
all?

Solution: Distance covered by bus = 15.75 km

Distance covered by walking = + 2.50 km
Total distance covered = 18.25 km

Example 14: Naseem’s mother gave him ` 20.50 and his grandmother gave him ` 30.40. Find the
total amount given to Naseem.

Solution: Money given by Naseem’s mother = ` 20.50

Money given by Naseem’s grandmother = + ` 30.40
Total money given to Naseem = ` 50.90

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