NCERT Class 6 Maths Chapter 8 Decimals Exercise 8.4

Chapter 8 Decimals Exercise 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 = 100 paise
= 5/100
= ₹0.05

b)
₹1 = 100 paise
= 75/100
= ₹0.75

c)
₹1 = 100 paise
= 20/100
= ₹0.20

d)
₹1 = 100 paise
= 90/100
= ₹0.90
= ₹50 + ₹0.90
= ₹50.90

e)
₹1 = 100 paise
= 725/100
= ₹7.25

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
Answer:
a)
1 m = 100 cm
= 15/100
= 0.15 m

b)
1 m = 100 cm
= 6/100
= 0.06 m

c)
1 m = 100 cm
= 45/100
= 0.45 m
= 2 m + 0.45 m
= 2.45 m

d)
1 m = 100 cm
= 7/100
= 0.07 m
= 9 m + 0.07 m
= 9.07 m

e)
1 m = 100 cm
= 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 cm = 10 mm
= 5/10
= 0.5 cm

b)
1 cm = 10 mm
= 60/10
= 6.0 cm

c)
1 cm = 10 mm
= 164/10
= 16.4 cm

d)
1 cm = 10 mm
= 8/10
= 0.8 cm
= 9 cm + 0.8 cm
= 9.8 cm

e)
1 cm = 10 mm
= 93/10
= 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 km = 1000 m
= 8/1000
= 0.008 km

b)
1 km = 1000 m
= 88/1000
= 0.088 km

c)
1 km = 1000 m
= 8888/1000
= 8.888 km

d)
1 km = 1000 m
= 5/1000
= 0.005 km
= 70 km + 0.005 km
= 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 kg = 1000 g
= 2/1000
= 0.002 kg

b)
1 kg = 1000 g
= 100/1000
= 0.010 kg

c)
1 kg = 1000 g
= 3750/1000
= 3.750 kg

d)
1 kg = 1000 g
= 8/1000
= 0.008 kg
= 5 kg + 0.008 kg
= 5.008 kg

e)
1 kg = 1000 g
= 50/1000
= 0.050 kg
= 26 kg + 0.050 kg
= 26.050 kg