RBSE Solutions for Class 7 Maths Chapter 8 Comparing Quantities Ex 8.1

Rajasthan Board RBSE Solutions for Class 7 Maths Chapter 8 Comparing Quantities Ex 8.1 Textbook Exercise Questions and Answers.

RBSE Class 7 Maths Solutions Chapter 8 Comparing Quantities Ex 8.1

Question 1.
Find the ratio of:
(a) ₹ 5 to 50 paise
Answer:
₹ 5 to 50 paise
₹ 5 = 5 × 100 paise = 500 paise
∴ The ratio of ₹ 5 to 50 paise
= 500 : 50 = 10 : 1

(b) 15 kg to 210 g
Answer:
15 kg to 210 g
15 kg = 15 × 1000 g = 15000 g
∴ The ratio of 15 kg to 210 g
= 15000 : 210 = 500 : 7

(c) 9 m to 27 cm
Answer:
9 m to 27 cm 9 m
= 9 × 100 cm = 900 cm
∴ The ratio of 9 m to 27 cm
= 900 : 27 = 100 : 3

(d) 30 days to 36 hours
Answer:
30 days to 36 hours
30 days = 30 × 24 hours = 720 hours
∴ The ratio of 30 days to 36 hours
= 720 : 36 = 20 : 1

Question 2.
In a computer lab, there are 3 computers for every 6 students. How many computers will be needed for 24 students?
Answer:
Let x computers be needed for 24 students.
Then 3 : x = 6 : 24
⇒ \(\frac{3}{x}=\frac{6}{24}\) ⇒ 6x = 24 × 3 ⇒ 6x = 72
⇒ x = \(\frac{72}{6}\) ⇒ x = 12
∴ 12 computers are needed for 24 students.

Question 3.
Population of Rajasthan = 570 lakh and population of UP = 1660 lakh. Area of Rajasthan = 3 lakh km² and area of UP = 2 lakh km².
(i) How many people are there per km² in both these States?
(ii) Which State is less populated?
Answer:
(i) Population of Rajasthan = 570 lakhs.
Area of Rajasthan = 3 lakh km².
Number of people per km² in Rajasthan state = \(\frac{570}{3}\) = 190 people/km²
Population of UP = 1660 lakh.
Area of UP =2 lakh km².
∴ Number of people per km² in UP State 1060
= 2 = 830 people/km²

(ii) Rajasthan is less populated.