New Learning Composite Mathematics Class 6 SK Gupta Anubhuti Gangal Ratio Proportion and Unitary Method Chapter 8F Solution
(1) Cost of 20 m of cloth = RS 1600
Cost of 1 m of cloth = RS 1600/20
= RS 80
∴ Cost of 28 m of cloth = RS (80X28)
= RS 2240
Ans – Cost of 28m of cloth is RS 2240
(2) Cost of 8 kg of potatoes = RS 46.56
Cost of 1kg of potatoes = RS 46.56/8
= RS 5.82
∴ Cost of 15 kg of potatoes = RS (5.82X15)
= RS 87.3
(3) Cost of 12 pens = RS 120
Cost of 1 pen = RS 120/12
= RS 10
∴ Cost of 20 pens = RS (10X20)
= RS 200
(4) IN 30L petrol a car travels = 540 km
In 1L petrol a car travels = 540/30 km
= 18 km
∴ In 20L petrol a car travels = (18X20) km
= 360km
(5) Every 15000 light bulbs produced, 60 were faulty
1 light bulbs produced, 60/15000 were faulty
In 6000 light bulbs produced no of faulty
Bulbs = 60X6000/15000
= 24
(6) (a) First one per kg = 35.50/5
= Rs. 7.10
Second one per kg = RS 18.60/3
= RS 6.20
Ans – 3 kg for RS 18.60 is better to buy.
(b) First one, cost of one pen = RS 158/10
= RS 15.8
Second one, cost one pen = RS 136/8
= RS 17
Ans – 10 pens for RS 158 is better to buy
(10) Sachin’s performance in 1 over = 60/5 runs
= 12 runs
Rohit’s performance in 1 over = 72/8 runs
= 9 runs
Ans – Sachin’s performance is better than Rohit’s.