Page 105 - ICSE Math 5

Applications of Decimals in Real Life Situations

Decimals are used when we talk about money, length, weight, etc.

• We use notes and coins while dealing with money.
1
1 rupee = 100 paise or 1 paisa = rupee = ` 0.01
100
• We use metre, centimetre and kilometre to measure length and distance. We know that
the standard unit of length is metre.
1 1
1 m = 100 cm or 1 cm = m = 0.01 m 1 km = 1,000 m or 1 m = km = 0.001 km
100 1000
• We use kilograms to measure heavy objects and grams for measuring lighter objects.
1
1 kg = 1,000 g or 1 g = kg = 0.001 kg
1000
Word Problems on Addition and Subtraction of Decimals

Let’s solve the given word problems on addition and subtraction of decimals.
Example 11: Radhika had ` 6,400 with her. She spent ` 2,461.25, ` 585.25 and ` 636.50
respectively on three consecutive days. How much money was she left with?

Solution: Total money Radhika had = ` 6,400 Calculation
Money spent on first day = ` 2,461.25 1 1 1 1 1
2461 . 25
Money spent on second day = ` 585.25
585 . 25
Money spent on third day = ` 636.50 + 636 . 50

 Total money spent by Radhika 3683 . 00
= ` (2,461.25 + 585.25 + 636.50) = ` 3683.00 13 9
5 3 10 10
Money left with Radhika 6400
= ` (6,400 – 3,683) = ` 2,717 – 3683
2717
So, the money left with Radhika was ` 2,717.
Example 12: Sunaina travelled 18 km 343 m by bus, 4 km 15 m by auto and finally walked 208 m
to reach her friend’s home. What is the total distance travelled by her?
Solution: Distance travelled by Sunaina by bus = 18 km 343 m
Calculation
343
= 18 km + km = 18.343 km 1 1
1000 18 . 343
Distance travelled by Sunaina by auto = 4 km 15 m 4 . 015
15 + 0 . 208
= 4 km + km = 4.015 km
1000 22 . 566
Distance travelled by Sunaina on foot = 208 m
208
= km = 0.208 km Top Tip
1000
 Total distance travelled by Sunaina While solving word
problems, make sure all the
= (18.343 + 4.015 + 0.208) km = 22.566 km quantities in the question
So, Sunaina travelled 22.566 km or 22 km 566 m. are in the same unit.

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