Class 6 - Mathematics : Decimals
Exercise : 8.4
Top Block 1
NCERT Solutions Class 6 Mathematics Decimals 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
Answer :
(a) ∵ 1 paisa = Rs.1⁄100
∴ 5 paise = (1⁄100) x 5 = Rs. 0.05
(b) ∵ 1 paisa = Rs.1⁄100
∴ 75 paise = (1⁄100) x 5 = Rs. 0.75
(c) ∵ 1 paisa = Rs.1⁄100
∴ 20 paise = (1⁄100) x 5 = Rs. 0.05
(d) ∵ 1 paisa = Rs.1⁄100
∴Rs. 50 + 90 paise = 50 +(1⁄100) x 90 = Rs. 50.90
(e) ∵ 1 paisa = Rs.1⁄100
∴ 725 paise = (1⁄100) x 725 =(725⁄100) = Rs. 7.25
Question: 2.Express as meters using decimals:
(a) 15 cm
(b) 6 cm
(c) 2 m 45 cm
(d) 9 m 7 cm
(e) 419 cm
Answer :
(a) ∵ 1 cm = (1⁄100) m
∴ 15 cm = (1⁄100) x 15 = 0.15 m
(b) ∵ 1 cm = (1⁄100) m
∴ 6 cm = (1⁄100) x 6 = 0.06 m
(c) ∵ 1 cm = (1⁄100) m
∴ 2 m 45 cm = 2 + (1⁄100) x 45 = 2.45 m
(d) ∵ 1 cm = (1⁄100) m
∴ 9 m 7 cm = 9 +(1⁄100) x 7 = 9.07 m
(e) ∵ 1 cm = (1⁄100) m
∴ 419 cm = (1⁄100) x 419 = (419⁄100)= 4.19 m
Question: 3.Express as cm using decimals:
(a) 5 mm
(b) 60 mm
(c) 164 mm
(d) 9 cm 8 mm
(e) 93 mm
Answer :
(a) ∵ 1 mm = (1⁄10) cm
∴ 5 mm = (1⁄10) x 5 = 0.5 cm
(b) ∵ 1 mm = (1⁄10) cm
∴ 60 mm = (1⁄10) x 60 = 6 cm
(c) ∵ 1 mm = (1⁄10) cm
∴ 164 mm = (1⁄10) x 164 = 16.4 cm
(d) ∵ 1 mm = (1⁄10) cm
∴ 9 cm 8 mm = 9 + (1⁄10) x 8 = 9 + 0.8 = 9.8 cm
(e) ∵ 1 mm = (1⁄10) cm
∴ 93 mm = (1⁄10) x 93 = 9.3 cm
Question: 4.Express as km using decimals:
(a) 8 m
(b) 88 m
(c) 8888 m
(d) 70 km 5 m
Answer :
(a) ∵ 1 m = (1⁄1000) km
∴ 8 m = (1⁄1000) x 8 = 0.008 km
(b) ∵ 1 m = (1⁄1000) km
∴ 88 m = (1⁄1000) x 88 = 0.088 km
(c) ∵ 1 m = (1⁄1000) km
∴ 8888 m = (1⁄1000) x 8888 = 8.888 km
(d) ∵ 1 m = (1⁄1000) km
∴ 70 km 5 m = 70 + (1⁄1000) x 5 = 70.005 km
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
Answer :
(a) ∵ 1 g = (1⁄1000) kg
∴ 2 g = (1⁄1000) x 2 = 0.002 kg
(b) ∵ 1 g = (1⁄1000) kg
∴ 100 g = (1⁄1000) x 100 = 0.1 kg
(c) ∵ 1 g = (1⁄1000) kg
∴ 3750 g = (1⁄1000) x 3750 = 3.750 kg
(d) ∵ 1 g = (1⁄1000) kg
∴ 5 kg 8 g = 5 +(1⁄1000) x 8 = 5.008 kg
(e) ∵ 1 g = (1⁄1000) kg
∴ 26 kg 50 g = 26 +(1⁄1000) x 50 = 26.050 kg