DECIMALS
EXERCISE – 8.4
EX 8.4 QUESTION 1.
Express as rupees using decimals.
(a) 5 paise
(b) 75 paise
(c) 20 paise
(d) 50 rupees 90 paise
(e) 725 paise
Solution:
[100 paise = 1 rupees]
(a) 5 paise
= 5 / 100 rupees
= Rupess 0.05
(b) 75 paise
= 75 / 100 rupees
= Rupees 0.75
(c) 20 paise
= 20 / 100 rupees
= Rupees 0.20
(d) 50 rupees 90 paise
= [(50 + 90 / 100)] rupees
= Rupees 50.90
(e) 725 paise
= 725 / 100 rupees
= Rupees 7.25
EX 8.4 QUESTION 2.
Express as metres using decimals.
(a) 15 cm
(b) 6 cm
(c) 2 m 45 cm
(d) 9 m 7 cm
(e) 419 cm
Solution:
[100 cm = 1 metre]
(a) 15 cm
= 15 / 100 m
= 0.15 m
(b) 6 cm
= 6 / 100 m
= 0.06 m
(c) 2 m 45 cm
= [(2 + 45 / 100)] m
= 2.45 m
(d) 9 m 7 cm
= [(9 + 7 / 100)] m
= 9.07 m
(e) 419 cm = 419 / 100 m
= 4.19 m
EX 8.4 QUESTION 3.
Express as cm using decimals
(a) 5 mm
(b) 60 mm
(c) 164 mm
(d) 9 cm 8 mm
(e) 93 mm
Solutions:
[10 mm = 1 cm]
(a) 5 mm = 5 / 10 cm
= 0.5 cm
(b) 60 mm = 60 / 10 cm
= 6.0 cm
(c) 164 mm = 164 / 10 cm
= 16.4 cm
(d) 9 cm 8 mm = [(9 + 8 / 10)] cm
= 9.8 cm
(e) 93 mm = 93 / 10 cm
= 9.3 cm
EX 8.4 QUESTION 4.
Express as km using decimals.
(a) 8 m
(b) 88 m
(c) 8888 m
(d) 70 km 5 m
Solutions:
[1000 metres = 1 km]
(a) 8 m = 8 / 1000 km
= 0.008 km
(b) 88 m = 88 / 1000 km
= 0.088 km
(c) 8888 m = 8888 / 1000 km
= 8.888 km
(d) 70 km 5 m = [(70 + 5 / 1000)] km
= 70.005 km
EX 8.4 QUESTION 5.
Express as kg using decimals.
(a) 2 g
(b) 100 g
(c) 3750 g
(d) 5 kg 8 g
(e) 26 kg 50 g
Solutions:
[1000 grams = 1 kg]
(a) 2 g = 2 / 1000 kg
= 0.002 kg
(b) 100 g = 100 / 1000 kg
= 0.1 kg
(c) 3750 g = 3750 / 1000 kg
= 3.750 kg
(d) 5 kg 8 g = [(5 + 8 / 1000)] kg
= 5.008 kg
(e) 26 kg 50 g = [(20 + 50 / 1000)] kg
= 26.050 kg
