NCERT Solution For Class 6, Maths, Chapter 12, Ratio And Proportion, Exercise 12.3 has questions of comparisons in ratio and proportions. Exercise 12.3, class 6 maths involves questions of day to day life like finding to unknown values, cost, money earned in 1 month etc. NCERT class 6 maths, ch.12 ratio and proportion has total eleven exercise to study.
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NCERT Solution For Class 6, Maths, Chapter 12, Ratio And Proportion, Exercise 12.3
Q.1. If the cost of 7 m of cloth is ₹1470, find the cost of 5 m of cloth.
Ans: Cost of 7 m cloth = ₹ 1470
Cost of 1 m cloth = 1470 ÷ 7 = ₹ 210
So, cost of 5 cloth = 210 × 5 = ₹ 1050
Thus, Cost of 5 m cloth is ₹ 1050.
Q.2. Ekta earns ₹3000 in 10 days. How much will she earn in 30 days?
Ans: Money earned in 10 days = ₹ 3000
Money earned in one day = 3000÷10 = ₹ 300
So, money earned by her in 30 days = 300 × 30 = ₹ 9000
Q.3. If it has rained 276 mm in the last 3 days, how many cm of rain will fall in one full week (7 days)? Assume that the rain continues to fall at the same rate.
Ans: Rain in 3 days = 276 mm
∴ Rain in 1 day = 276÷3 = 92 mm
So, rain in one week (7 days ) = 92×7 = 644 mm
= 644 ÷ 10 [∵1 cm = 10 mm or 1 mm = 1/10 cm]
= 64.4 cm
Thus, the rain in one week (7 days) is 64.4 cm.
Q.4. Cost of 5 kg of wheat is ₹ 91.50.
(a) What will be the cost of 8 kg of wheat?
(b) What quantity of wheat can be purchased in ₹ 183?
Ans: (a) Cost of 5 kg wheat = ₹ 91.50.
∴ Cost of 1 kg wheat = $\frac{91.50}{5}$ = ₹ 18.3
So, cost of 8 kg wheat = 18.3×8 = ₹ 146.40
(b) Wheat purchased in ₹ 91.50 = 5 kg
Wheat purchased in ₹1 $=\frac{5}{91.50}$kg
So, wheat purchased in ₹ 183 $=\frac{5}{91.50}\times183\,=\frac{5\,\times \,10}{5}\times \,1\,=\,10\,kg$
Thus, 10 kg wheat can be purchased in ₹ 183.
Q.5. The temperature dropped 15 degree Celsius in the last 30 days. If the rate of temperature drop remains the same, how many degrees will the temperature drop in the next ten days?
Ans: Temperature drop in 30 days = 150 C
Temperature drop in 1 day = 15/30 = (1/2)0 C
So, temperature drop in next 10 days = (1/2) ×10 = 50 C
Thus, The temperature drop in the next 10 days will be 50 C
Q.6. Shaina pays ₹ 15000 as rent for 3 months. How much does she has to pay for a whole year, if the rent per month remains same?
Ans: Rent paid for 3 months = ₹ 15000
Rent for 1 month = 15000/3 = ₹ 5000
So, rent for 12 months (1 year) = 5000×12 = ₹ 60,000
Thus, Rent paid by Shaina in 1 year is ₹ 60,000
Q.7. Cost of 4 dozen bananas is ₹ 180. How many bananas can be purchased for ₹ 90?
Ans: Number of bananas bought in₹ 180 = 4 dozens = 4 × 12 = 48 bananas
Number of bananas bought in ₹ 1 = $\frac{48}{180}$
So, number of bananas bought in ₹ 90 = (48/180) × 90 = 24 bananas
Thus, 24 bananas (2 dozen) can be purchased in ₹ 90
Q.8. The weight of 72 books is 9 kg. What is the weight of 40 such books?
Ans: Weight of 72 books = 9 kg
Weight of 1 book = 9/72 = 1/8 kg
So, weight of 40 books = (1/8) × 40 = 5 kg
Thus, Weight of 40 books is 5 kg
Q.9. A truck requires 108 litres of diesel for covering a distance of 594 km. How much diesel will be required by the truck to cover a distance of 1650 km?
Ans: Diesel required to cover 594 km distance = 108 litres
∴ Diesel required to cover 1km distance $=\frac{108}{594}=\frac{108\,\div \,\,54}{594\,\div \,\,54}=\frac{2}{11}\,$Litre
So, diesel required for 1650 km $=\frac{2}{11}\,\times 1650\,= 2\times \,150\,=\,300\,$Litre
Thus, Diesel required by the truck to cover a distance of 1650 km is 300 litres.
Q.10. Raju purchases 10 pens for ₹ 150 and Manish buys 7 pens for ₹ 84. Can you say who got the pens cheaper?
Ans: Raju purchases 10 pens for = ₹ 150
∴ Cost of 1 pen = 150/10 = ₹ 15
Manish purchases 7 pens for = ₹ 84
∴ Cost of 1 pen = 84/7 = ₹ 12
Thus , Pens purchased by Manish are cheaper than Raju.
Q.11. Anish made 42 runs in 6 overs and Anup made 63 runs in 7 overs. Who made more runs per over?
Ans: Runs made by Anish in 6 overs = 42
∴ Runs made by Anish in 1over = 42/6 = 7
Runs made by Anup in 7 overs = 63
∴ Runs made by Anup in 1over = 63/7 = 9
Thus, Anup made more runs per over than Anish.