Students can Download Class 7 Maths Chapter 8 Comparing Quantities Ex 8.2 Questions and Answers, Notes Pdf, KSEEB Solutions for Class 7 Maths helps you to revise the complete Karnataka State Board Syllabus and to clear all their doubts, score well in final exams.
Karnataka State Syllabus Class 7 Maths Chapter 8 Comparing Quantities Ex 8.2
Question 1.
Convert the given fractional numbers to percents.
a)
Solution:
Percent means per hundred. So multi-plied by 100.
b)
Solution:
c)
Solution:
d)
Solution:
Converting the fraction 9/20 as a decimal is very easy.
Question 2.
Convert the given decimal fractions to per cents.
a) 0.65
Solution:
b) 2.1
Solution:
c) 0.02
Solution:
d) 12.35
Solution:
Question 3.
Estimate what part of the figures is coloured and hence find the per cent which is coloured. (a) 0.65, (b) 2.1, (c) 0.02, (d) 12.35.
Solution:
(i) \(\frac{1}{4}\) of the figure is coloured.
∴ 25% of the figure is coloured.
(ii) \(\frac{3}{5}\) of the figure is coloured.
∴ in the second figur e 60% Is coloured.
(iii) \(\frac{3}{8}\) of the figure is coloured.
∴ In the third figure 37.5 % is coloured.
Question 4.
Find :
a) 15% of 250
Solution:
b) 1% of 1 hour
Solution:
∴ 1% of 1 hour is \(\frac{3}{5}\) minutes or 36 seconds.
c) 20% of ₹ 2500
Solution:
We have, 20% of ₹ 2500
\(\frac{20}{100}\) × 2500 = ₹ 500
∴ 20% of ₹ 2500 is ₹ 500.
d) 75% of 1 kg
Solution:
We have, 75% of 1 kg
\(\frac{75}{100}\) × 1000 = 750 g
∴ 75% of 1 kg is 750 g.
Question 5.
Find the whole quantity if
a) 5% of it is 600.
Solution:
Let the whole quantity be ‘m’
∴ 5% of m = 600
∴ The whole quantity is 12,000.
b) 12% of its 1080.
Solution:
Let the whole quantity be ‘m’
∴ 12% of m = Rs. 1080
∴ The whole amount be Rs. 9.000
c) 40 % of it is 500 km
Solution:
Let the whole quantity be ‘m’
∴ 40% of m = 500 km
∴ The whole amount is 1250 kms
d) 70% of it is 14 minutes
Solution:
Let the whole quantity be ‘m’
∴ The whole amount is 20 minutes
e) 8% of it is 40 litres.
Solution:
Let the whole quantity be ‘m’
∴ The whole amount be 500 liters
Question 6.
Convert given per cents to decimal fractions and also to fractions in simplest forms:
Solution:
(a) 25%
(b) 150%
(c) 20%
(d) 5%
Question 7.
In a city, 30% are females, 40% are males, and the remaining are children. What percent are children?
Solution:
females = 30%
males = 40%
= 100 – (30 + 40)
remaining are children = 100 – 70 = 30%
∴ Percentage of children = 30%
Convert cgpa to percentage according mumbai university rule.
Question 8.
Out of 15,000 votes in a constituency, 60% voted. Find the percentage of voters who did not vote. Can you now find how many actually did not vote?
Solution:
Total no. of voters in a constituency = 15,000
Percentage of voted = 60%
∴ Percentage of voters who did not vote
= 100 – 60 = 40%
Actual number of voters who did not vote} = 40% of 15,000
6000 voters who did not vote.
Question 9.
Meeta saves ₹ 400 from her salary. If this is 10% of her salary. What is her salary?
Solution:
Let Meeta’s salary be ‘M’
10% of M is = Rs. 400
∴ M =?
∴ Her salary be 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?
Solution:
Let the total matches won by them be M 25% of 20 = M
∴ They win 5 matches.