## MP Board Class 7th Maths Solutions Chapter 8 Comparing Quantities Ex 8.1

Question 1.

Find the ratio of:

(a) ₹ 5 to 50paise

(b) 15 kg to 210 g

(c) 9 m to 27 cm

(d) 30 days to 36 hours

Solution:

(a) ₹ 5 to 50 paise

1 rupee = 100 paise

∴ 5 rupee = 500 paise

Hence, the required ratio is

(b) 15 kg to 210 g

1kg = 1000g

15 kg = 15000 g

Hence, the required ratio is

(c) 9 m to 27 cm

1m = 100 cm

9 m = 900 cm

Hence, the required ratio is

(d) 30 days to 36 hours

1 day = 24 hours

30 days = 24 × 30 = 720 hrs

Hence, the required ratio is

Question 2.

In a computer lab, there are 3 computers for every 6 students. How many computers will

be needed for 24 students?

Solution:

For 6 students, number of computers required = 3

For 1 student, number of computers required = \(\frac{3}{6}\)

For 24 students, number of computers required = \(24 \times \frac{3}{6}=12\)

Hence, 12 computers are required for 24 students.

Question 3.

Population of Rajasthan = 570 lakhs and population of UP = 1660 lakhs.

Area of Rajasthan = 3 lakhs km^{2} and Area of UP = 2 lakhs km^{2}

(i) How many people are there per km^{2} in both these states ?

(ii) Which states is less populated?

Solution:

(i) Population of Rajasthan in 3 lakhs km^{2}

area = 570 lakhs

Population of rajasthan in 1 km^{2} area

\(=\frac{570}{3}=190\) lakhs

Population of U.P. in 2 km^{2} = 1660 lakhs

Population of U.P. in 1 km^{2} = \(\frac{1660}{2}\)

= 830 lakhs

(ii) It can be observed that population per km^{2} area is lesser for Rajasthan. Therefore, Rajasthan is less populated.