Fractions and Decimals Ex-2.7

NCERT solutions for Maths Fractions and Decimals 

NCERT Solutions for Class 7 Maths Fractions and Decimals

Class –VII Mathematics (Ex. 2.7)

Question 1.Find:

(i) 0.4 $\div$ 2

(ii) 0.35 $\div$ 5

(iii) 2.48 $\div$ 4

(iv) 65.4 $\div$ 6

(v) 651.2 $\div$ 4

(v) 14.49 $\div$ 7

(vii) 3.96 $\div$ 4

(viii) 0.80 $\div$ 5

Answer:

(i) 0.4 $\div$ 2 = $\frac{4}{{10}} \times \frac{1}{2} = \frac{2}{{10}}$ = 0.2

(ii) 0.35 $\div$ 5 = $\frac{{35}}{{100}} \times \frac{1}{5} = \frac{7}{{100}}$ = 0.07

(iii)2.48 $\div$ 4 = $\frac{{248}}{{100}} \times \frac{1}{4} = \frac{{62}}{{100}}$ = 0.62 (iv) 65.4 $\div$ 6 = $\frac{{654}}{{10}} \times \frac{1}{6} = \frac{{109}}{{10}}$ = 10.9

(v)651.2 $\div$ 4 = $\frac{{6512}}{{10}} \times \frac{1}{4} = \frac{{1628}}{{10}}$ = 162.8

(vi)14.49 $\div$ 7 = $\frac{{1449}}{{100}} \times \frac{1}{7} = \frac{{207}}{{100}}$ = 2.07

(vii)3.96 $\div$ 4 = $\frac{{396}}{{100}} \times \frac{1}{4} = \frac{{99}}{{100}}$ = 0.99

(viii)0.80 $\div$ 5 = $\frac{{80}}{{100}} \times \frac{1}{5} = \frac{{16}}{{100}}$ = 0.16

NCERT Solutions for Class 7 Maths Exercise 2.7

Question 2.Find:

(i) 4.8 $\div$ 10

(ii) 52.5 $\div$ 10

(iii) 0.7 $\div$ 10

(iv) 33.1 $\div$ 10

(v) 272.23 $\div$ 10

(vi) 0.56 $\div$ 10

(vii) 3.97 $\div$ 10

Answer:

(i) 4.8 $\div$ 10 = $\frac{{4.8}}{{10}}$ = 0.48

(ii) 52.5 $\div$ 10 = $\frac{{52.5}}{{10}}$ = 5.25

(iii) 0.7 $\div$ 10 = $\frac{{0.7}}{{10}}$ = 0.07

(iv) 33.1 $\div$ 10 = $\frac{{33.1}}{{10}}$ = 3.31

(v) 272.23 $\div$ 10 = $\frac{{272.23}}{{10}}$ = 27.223

(vi) 0.56 $\div$ 10 = $\frac{{0.56}}{{10}}$ = 0.056

(vii) 3.97 $\div$ 10 = $\frac{{3.97}}{{10}}$ = 0.397

NCERT Solutions for Class 7 Maths Exercise 2.7

Question 3. Find:

(i) 2.7 $\div$ 100

(ii) 0.3 $\div$ 100

(iii) 0.78 $\div$ 100

(iv) 432.6 $\div$ 100

(v) 23.6 $\div$ 100

(vi) 98.53 $\div$ 100

Answer:

(i) 2.7 $\div$ 100 = $\frac{{27}}{{10}} \times \frac{1}{{100}} = \frac{{27}}{{1000}}$ = 0.027

(ii) 0.3 $\div$ 100 = $\frac{3}{{10}} \times \frac{1}{{100}} = \frac{3}{{1000}}$ = 0.003

(iii) 0.78 $\div$ 100 = $\frac{{78}}{{100}} \times \frac{1}{{100}} = \frac{{78}}{{10000}}$ = 0.0078

(iv) 432.6 $\div$ 100 = $\frac{{4326}}{{10}} \times \frac{1}{{100}} = \frac{{4326}}{{1000}}$ = 4.326

(v) 23.6 $\div$ 100 = $\frac{{236}}{{10}} \times \frac{1}{{100}} = \frac{{236}}{{1000}}$ = 0.236

(vi) 98.53 $\div$ 100 = $\frac{{9853}}{{100}} \times \frac{1}{{100}} = \frac{{9853}}{{10000}}$ 0.9853

NCERT Solutions for Class 7 Maths Exercise 2.7

Question 4.Find:

(i) 7.9 $\div$ 1000

(ii) 26.3 $\div$ 1000

(iii) 38.53 $\div$ 1000

(iv) 128.9 $\div$ 1000

(v) 0.5 $\div$ 1000

Answer:

(i) 7.9 $\div$ 1000 = $\frac{{79}}{{10}} \times \frac{1}{{1000}} = \frac{{79}}{{10000}}$ = 0.0079

(ii) 26.3 $\div$ 1000 = $\frac{{263}}{{10}} \times \frac{1}{{1000}} = \frac{{263}}{{10000}}$ = 0.0263

(iii) 38.53 $\div$ 1000 = $\frac{{3853}}{{100}} \times \frac{1}{{1000}} = \frac{{3853}}{{100000}}$ = 0.03853

(iv) 128.9 $\div$ 1000 = $\frac{{1289}}{{10}} \times \frac{1}{{1000}} = \frac{{1289}}{{10000}}$ = 0.1289

(v) 0.5 $\div$ 1000 = $\frac{5}{{10}} \times \frac{1}{{1000}} = \frac{5}{{10000}}$ = 0.0005

NCERT Solutions for Class 7 Maths Exercise 2.7

Question 5.Find:

(i) 7 $\div$ 3.5

(ii) 36 $\div$ 0.2

(iii) 3.25 $\div$ 0.5

(iv) 30.94 $\div$ 0.7

(v) 0.5 $\div$ 0.25

(vi) 7.75 $\div$ 0.25

(vii) 76.5 $\div$ 0.15

(viii) 37.8 $\div$ 1.4

(ix) 2.73 $\div$ 1.3

Answer:

(i) 7 $\div$ 3.5 = $7 \div \frac{{35}}{{10}} = 7 \times \frac{{10}}{{35}} = \frac{{10}}{5}$ = 2

(ii) 36 $\div$ 0.2 = $36 \div \frac{2}{{10}} = 36 \times \frac{{10}}{2} =$ 18 x 10 = 180

(iii) 3.25 $\div$ 0.5 = $\frac{{325}}{{100}} \div \frac{5}{{10}} = \frac{{325}}{{100}} \times \frac{{10}}{5} = \frac{{65}}{{10}}$ = 6.5

(iv) 30.94 $\div$ 0.7 = $\frac{{3094}}{{100}} \div \frac{7}{{10}} = \frac{{3094}}{{100}} \times \frac{{10}}{7} = \frac{{442}}{{10}}$ = 44.2

(v) 0.5 $\div$ 0.25 = $\frac{5}{{10}} \div \frac{{25}}{{100}} = \frac{5}{{10}} \times \frac{{100}}{{25}} = \frac{{10}}{5}$ = 2

(vi) 7.75 $\div$ 0.25 = $\frac{{775}}{{100}} \div \frac{{25}}{{100}} = \frac{{775}}{{100}} \times \frac{{100}}{{25}}$ = 31

(vii) 76.5 $\div$ 0.15 = $\frac{{765}}{{10}} \div \frac{{15}}{{100}} = \frac{{765}}{{10}} \times \frac{{100}}{{15}}$ = 51 x 10 = 510

(viii) 37.8 $\div$ 1.4 = $\frac{{378}}{{10}} \div \frac{{14}}{{10}} = \frac{{378}}{{10}} \times \frac{{10}}{{14}}$ = 27

(ix) 2.73 $\div$ 1.3 = $\frac{{273}}{{100}} \div \frac{{13}}{{10}} = \frac{{273}}{{100}} \times \frac{{10}}{{13}} = \frac{{21}}{{10}}$ = 2.1

NCERT Solutions for Class 7 Maths Exercise 2.7

Question 6.A vehicle covers a distance of 43.2 km in 2.4 litres of petrol. How% much distance will it cover in one litre petrol?

Answer:

$\because$ In 2.4 litres of petrol, distance covered by the vehicle = 43.2 km

$\therefore$ In 1 litre of petrol, distance covered by the vehicle = 43.2 $\div$ 2.4

= $\frac{{432}}{{10}} \div \frac{{24}}{{10}}$ = $\frac{{432}}{{10}} \times \frac{{24}}{{10}}$

= 18 km

Thus, it covered 18 km distance in one litre of petrol.