Decimal Fractions — Exercise 7(D)

Express in paise:

(i) ₹ 8.40

(ii) ₹ 0.97

(iii) ₹ 0.09

(iv) ₹ 62.35

Answer

Since ₹ 1 = 100 paise, we multiply the amount in rupees by 100.

(i) ₹ 8.40 = 8.40 × 100 paise = 840 p

Hence, ₹ 8.40 = 840 p

(ii) ₹ 0.97 = 0.97 × 100 paise = 97 p

Hence, ₹ 0.97 = 97 p

(iii) ₹ 0.09 = 0.09 × 100 paise = 9 p

Hence, ₹ 0.09 = 9 p

(iv) ₹ 62.35 = 62.35 × 100 paise = 6235 p

Hence, ₹ 62.35 = 6235 p

Express in rupees:

(i) 55 p

(ii) 8 p

(iii) 695 p

(iv) 3279 p

Answer

Since 100 paise = ₹ 1, we divide the amount in paise by 100.

(i) 55 p = ₹ $\dfrac{55}{100}$ = ₹ 0.55

Hence, 55 p = ₹ 0.55

(ii) 8 p = ₹ $\dfrac{8}{100}$ = ₹ 0.08

Hence, 8 p = ₹ 0.08

(iii) 695 p = ₹ $\dfrac{695}{100}$ = ₹ 6.95

Hence, 695 p = ₹ 6.95

(iv) 3279 p = ₹ $\dfrac{3279}{100}$ = ₹ 32.79

Hence, 3279 p = ₹ 32.79

Express in centimetre (cm):

(i) 6 m

(ii) 8.54 m

(iii) 3.08 m

(iv) 0.87 m

(v) 0.03 m

(vi) 25.04 m

Answer

Since 1 m = 100 cm, we multiply the length in metre by 100.

(i) 6 m = 6 × 100 cm = 600 cm

Hence, 6 m = 600 cm

(ii) 8.54 m = 8.54 × 100 cm = 854 cm

Hence, 8.54 m = 854 cm

(iii) 3.08 m = 3.08 × 100 cm = 308 cm

Hence, 3.08 m = 308 cm

(iv) 0.87 m = 0.87 × 100 cm = 87 cm

Hence, 0.87 m = 87 cm

(v) 0.03 m = 0.03 × 100 cm = 3 cm

Hence, 0.03 m = 3 cm

(vi) 25.04 m = 25.04 × 100 cm = 2504 cm

Hence, 25.04 m = 2504 cm

Express in metre (m):

(i) 250 cm

(ii) 2328 cm

(iii) 86 cm

(iv) 4 cm

(v) 107 cm

Answer

Since 100 cm = 1 m, we divide the length in cm by 100.

(i) 250 cm = $\dfrac{250}{100}$ m = 2.50 m

Hence, 250 cm = 2.50 m

(ii) 2328 cm = $\dfrac{2328}{100}$ m = 23.28 m

Hence, 2328 cm = 23.28 m

(iii) 86 cm = $\dfrac{86}{100}$ m = 0.86 m

Hence, 86 cm = 0.86 m

(iv) 4 cm = $\dfrac{4}{100}$ m = 0.04 m

Hence, 4 cm = 0.04 m

(v) 107 cm = $\dfrac{107}{100}$ m = 1.07 m

Hence, 107 cm = 1.07 m

Express in gram (g):

(i) 6 kg

(ii) 5.543 kg

(iii) 0.078 kg

(iv) 3.62 kg

(v) 4.5 kg

Answer

Since 1 kg = 1000 g, we multiply the mass in kg by 1000.

(i) 6 kg = 6 × 1000 g = 6000 g

Hence, 6 kg = 6000 g

(ii) 5.543 kg = 5.543 × 1000 g = 5543 g

Hence, 5.543 kg = 5543 g

(iii) 0.078 kg = 0.078 × 1000 g = 78 g

Hence, 0.078 kg = 78 g

(iv) 3.62 kg = 3.62 × 1000 g = 3620 g

Hence, 3.62 kg = 3620 g

(v) 4.5 kg = 4.5 × 1000 g = 4500 g

Hence, 4.5 kg = 4500 g

Express in kilogram (kg):

(i) 7000 g

(ii) 6839 g

(iii) 445 g

(iv) 93 g

(v) 8 g

(vi) 13545 g

Answer

Since 1000 g = 1 kg, we divide the mass in g by 1000.

(i) 7000 g = $\dfrac{7000}{1000}$ kg = 7 kg

Hence, 7000 g = 7 kg

(ii) 6839 g = $\dfrac{6839}{1000}$ kg = 6.839 kg

Hence, 6839 g = 6.839 kg

(iii) 445 g = $\dfrac{445}{1000}$ kg = 0.445 kg

Hence, 445 g = 0.445 kg

(iv) 93 g = $\dfrac{93}{1000}$ kg = 0.093 kg

Hence, 93 g = 0.093 kg

(v) 8 g = $\dfrac{8}{1000}$ kg = 0.008 kg

Hence, 8 g = 0.008 kg

(vi) 13545 g = $\dfrac{13545}{1000}$ kg = 13.545 kg

Hence, 13545 g = 13.545 kg

Add, giving answer in rupees:

(i) ₹ 5.37 and ₹ 12

(ii) ₹ 24.03 and 532 paise

(iii) 73 paise and ₹ 2.08

(iv) 8 paise and ₹ 15.36

Answer

Since 100 paise = ₹ 1, we first convert each amount into rupees (dividing paise by 100) so that all amounts are in the same unit, and then add.

(i) ₹ 5.37 + ₹ 12 = ₹ 5.37 + ₹ 12.00 = ₹ 17.37

Hence, the sum = ₹ 17.37

(ii) 532 paise = ₹ 5.32

₹ 24.03 + ₹ 5.32 = ₹ 29.35

Hence, the sum = ₹ 29.35

(iii) 73 paise = ₹ 0.73

₹ 0.73 + ₹ 2.08 = ₹ 2.81

Hence, the sum = ₹ 2.81

(iv) 8 paise = ₹ 0.08

₹ 0.08 + ₹ 15.36 = ₹ 15.44

Hence, the sum = ₹ 15.44

Subtract:

(i) ₹ 35.74 from ₹ 63.22

(ii) 286 paise from ₹ 7.02

(iii) ₹ 0.55 from 121 paise

Answer

Since 100 paise = ₹ 1, we first convert each amount into rupees (dividing paise by 100) so that both amounts are in the same unit, and then subtract.

(i) ₹ 63.22 - ₹ 35.74 = ₹ 27.48

Hence, the difference = ₹ 27.48

(ii) 286 paise = ₹ 2.86

₹ 7.02 - ₹ 2.86 = ₹ 4.16

Hence, the difference = ₹ 4.16

(iii) 121 paise = ₹ 1.21

₹ 1.21 - ₹ 0.55 = ₹ 0.66 = 66 paise

Hence, the difference = ₹ 0.66 = 66 paise

Add, giving answer in metre:

(i) 2.4 m and 1.78 m

(ii) 848 cm and 2.9 m

(iii) 0.93 m and 64 cm

Answer

Since 100 cm = 1 m, we first convert each length into metre (dividing cm by 100) so that all lengths are in the same unit, and then add.

(i) 2.4 m + 1.78 m = 2.40 m + 1.78 m = 4.18 m

Hence, the sum = 4.18 m

(ii) 848 cm = 8.48 m

8.48 m + 2.90 m = 11.38 m

Hence, the sum = 11.38 m

(iii) 64 cm = 0.64 m

0.93 m + 0.64 m = 1.57 m

Hence, the sum = 1.57 m

Subtract, giving answer in metre:

(i) 5.03 m from 19.6 m

(ii) 428 cm from 1033 m

(iii) 0.84 m from 122 cm

Answer

Since 100 cm = 1 m, we first convert each length into metre (dividing cm by 100) so that both lengths are in the same unit, and then subtract.

(i) 19.6 m - 5.03 m = 19.60 m - 5.03 m = 14.57 m

Hence, the difference = 14.57 m

(ii) 428 cm = 4.28 m

1033 m - 4.28 m = 1028.72 m

Hence, the difference = 1028.72 m

(iii) 122 cm = 1.22 m

1.22 m - 0.84 m = 0.38 m

Hence, the difference = 0.38 m

Add, giving answer in kg:

(i) 2.06 kg and 57.864 kg

(ii) 778 g and 1.939 kg

(iii) 0.065 kg and 4023 g

Answer

Since 1000 g = 1 kg, we first convert each mass into kilogram (dividing g by 1000) so that all masses are in the same unit, and then add.

(i) 2.06 kg + 57.864 kg = 2.060 kg + 57.864 kg = 59.924 kg

Hence, the sum = 59.924 kg

(ii) 778 g = 0.778 kg

0.778 kg + 1.939 kg = 2.717 kg

Hence, the sum = 2.717 kg

(iii) 4023 g = 4.023 kg

0.065 kg + 4.023 kg = 4.088 kg

Hence, the sum = 4.088 kg

Subtract, giving answer in kg:

(i) 9.462 kg from 15.6 kg

(ii) 4317 g from 23 kg

(iii) 0.798 kg from 4169 g

Answer

Since 1000 g = 1 kg, we first convert each mass into kilogram (dividing g by 1000) so that both masses are in the same unit, and then subtract.

(i) 15.6 kg - 9.462 kg = 15.600 kg - 9.462 kg = 6.138 kg

Hence, the difference = 6.138 kg

(ii) 4317 g = 4.317 kg

23 kg - 4.317 kg = 23.000 kg - 4.317 kg = 18.683 kg

Hence, the difference = 18.683 kg

(iii) 4169 g = 4.169 kg

4.169 kg - 0.798 kg = 3.371 kg

Hence, the difference = 3.371 kg