Class 6 - Mathematics
Chapter - Comparing Quantities : Exercise 8.2
Top Block 1
Question: 1.Convert the given fractional numbers to percent:
(a) 1⁄8
(b) 5⁄4
(c) 3⁄40
(d) 2⁄7
Answer :
(a) 1⁄8 = 1⁄8 × 100% =25⁄2% = 12.5%
(b) 5⁄4 = 5⁄4 × 100% = 5 x 25% = 125%
(c) 3⁄40 = 3⁄40 × 100% = 3⁄2 × 5% = 15⁄2% = 7.5%
(d) 2⁄7 = 2⁄7 × 100% = 200⁄7% = 284⁄7%
Question: 2.Convert the given decimal fractions to percents:
(a) 0.65
(b) 2.1
(c) 0.02
(d) 12.35
Answer :
(a) 0.65 = 65⁄100 x 100% = 65%
(b) 2.1 = 210⁄100 x 100% = 210%
(c) 0.02 = 2⁄100 x 100% = 2%
(d) 12.35 = 1235⁄100 x 100% = 1235%
Question: 3.Estimate what part of the figures is coloured and hence find the percent which is coloured:
Answer :
(i) Coloured part = 1⁄4
Mddle block 1
(ii) Coloured part = 3⁄5
(iii) Coloured part = 3⁄8
= 37.5%
Question: 4.Find:
(a) 15% of 250
(b) 1% of 1 hour
(c) 20% of Rs. 2500
(d) 75% of 1 kg
Answer :
(a) 15% of 250 = 15⁄100 × 250 = 15 x 2.5 = 37.5
(b) 1% of 1 hours = 1% of 60 minutes = 1% of (60 x 60) seconds
= 1100×60×60 = 6 x 6 = 36 seconds
(c) 20% of Rs. 2500 = 20⁄100 × 2500 = 20 x 25 = Rs. 500
(d) 75% of 1 kg = 75% of 1000 g = 75⁄100 × 1000 = 750 g = 0.750 kg
Question: 5.Find the whole quantity if:
(a) 5% of it is 600
(b) 12% of it is Rs. 1080
(c) 40% of it is 500 km
(d) 70% of it is 14 minutes
(e) 8% of it is 40 liters
Answer :
Let the whole quantity be x in given Questions:
(a) 5% of x = 600 ⇒ 5⁄100 x x=600
⇒ x = 600 x 100⁄5 = 12,000
(b) 12% of x = Rs. 1080 ⇒ 12⁄100 x x=1080
⇒ x = 1080 x 100⁄12 = Rs. 9,000
(c) 40% of x = 500 km ⇒ 40⁄100 x x=500
⇒ x = 500 x 100⁄40 = 1,250 km
(d) 70% of x = 14 minutes ⇒ 70⁄100 x x=14
⇒ x = 14 x 100⁄40 = 20 minutes
(e) 8% of x = 40 liters ⇒ 8⁄100 x x = 40
⇒ x = 40 x 100⁄8 = 500 liters
Question: 6.Convert given percents to decimal fractions and also to fractions in simplest forms:
(a) 25%
(b) 150%
(c) 20%
(d) 5%
Answer :
| S. No. | Percents | Fractions | Simplest form | Decimal form |
|---|---|---|---|---|
| (a) | 25% | 25⁄100 | 1⁄4 | 0.25 |
| (b) | 150% | 150⁄100 | 3⁄2 | 1.5 |
| (c) | 20% | 20⁄100 | 1⁄5 | 0.2 |
| (d) | 5% | 5⁄100 | 1⁄20 | 0.05 |
Question: 7.In a city, 30% are females, 40% are males and remaining are children. What percent are children?
Answer :
Given: Percentage of females = 30%
Percentage of males = 40%
Total percentage of females and males = 30 + 40 = 70%
Percentage of children = Total percentage – Percentage of males and females
= 100% – 70%
= 30%
Hence, 30% are children.
Question: 8.Out of 15,000 voters in a constituency, 60^ voted. Find the percentage of voters who did not vote. Can you now find how many actually did not vote?
Answer :
Total voters = 15,000
Percentage of voted candidates = 60%
Percentage of not voted candidates = 100 – 60 = 40%
Actual candidates, who did not vote = 40% of 15000
= 40100×15000 = 6,000
Hence, 6,000 candidates did not vote.
Question: 9.Meeta saves Rs. 400 from her salary. If this is 10% of her salary. What is her salary?
Answer :
Let Meera’s salary be Rs.x.
Now, 10% of salary = Rs. 400
⇒ 10% of x = Rs. 400
⇒ 10⁄100 x x = 400
⇒ x = 400 x 100⁄10
⇒ x = 4,000
Hence, Meera’s salary is Rs. 4,000.
Question: 10.A local cricket team played 20 matches in one season. It won 25% of them. How many matches did they win?
Answer :
Number of matches played by cricket team = 20
Percentage of won matches = 25%
Total matches won by them = 25% of 20
= 25⁄100 x 20
= 5
Hence, they won 5 matches.