# Free Ncert Class 6 Math Ratio and Proportion Exercise 12.3

Ratio and Proportion Class 6 Ex. 12.3

Ratio and Proportion, Ncert Class 6, Chapter 12, Exercise 12.3 Math Free Solution.

Exercise 12.3

Question 1 :- If the cost of 7m of cloth is ₹ 1,470, find the cost of 5m of cloth.
Solution 1:-
Given that, cost of 7 m of cloth = ₹1,470;
The cost of 1 m of cloth is = ₹ 1,470/7
Cost of 5 m of cloth = ₹[(1,470/7)] x 5 = ₹(210 x 5) = ₹ 1050
Thus, the required cost = ₹ 1,050.

Question 2 :- Ekta earns ₹ 3000 in 10 days. How-much, will she earn in 30-days?
Solution 2:-
In 10 days Ekta earn ₹ 3,000;
In 1 days Ekta will earn ₹ (3,000/10) ;
In 30 days Ekta will earn ₹(3,000/10) x 30 = ₹9,000;
Hence, the money-earned by Ekta in 30 days = ₹9,000.

Question 3 :- If it has rained 276-mm in the last 3 days, how many-centimeter of rain will fall in one full week (7-days)? Assume that the rains continue to fall at the same-rate.
Solution 3:-
In last 3 days, the rain falls = 276 mm;
In 1 day, the rain falls = (276/3)mm;
In one week (7 days), the rain will fall = (276/3) x 7 mm;
= 92 x 7 mm = 644 mm or 64.4 cm                             [Since, 1 cm = 10 mm]
Hence, the amount of rain fall in a week(7 days) = 64.4 cm.

Question 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?
Solution 4:-
(a) The cost of 5-kg of wheat is = ₹ 91.50;
Cost of 1 kg of wheat = ₹ (91.50/5);
Cost of 8 kg of wheat = ₹ [(91.50/5) x 8] = 18.30 x 8 = ₹ 146.40;
Hence, the required cost = ₹ 146.40.

(b) The quantity of wheat purchased in ₹ 91.50 = 5 kg;
The quantity of wheat purchased in ₹ 1 = (5/91.50) kg;
The quantity of wheat purchased in ₹ 183 = [(5/91.50) x 183] kg;
So, the required quantity of wheat = 10 kg.

Question 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?
Solution 5:-
In last 30-days, temperature dropped = 15 degree Celsius;
For 1-day, the quantity of drop in temperature = (15/30) degree Celsius;
In last 10 days the quantity of drop is temperature = [(15/30) x 10] degree Celsius = 5 degree Celsius
Hence, the required drop in temperature in last 10 days = 5 degree Celsius.

Question 6 :- Shaina pays ₹ 15,000 as rent for 3 months. How-much does she has to pay, for a whole year, if the rent per month remains same?
Solution 6:-

Amount of rent paid in 3 months = ₹ 15,000;
Amount of rent paid in 1 month = ₹ (15,000/3);
Amount of rent paid in 12 months = ₹ [(15,000/3) x 12] = ₹ 60,000
So, the required amount of rent paid in 1 year = ₹ 60,000.

Question 7 :- Cost of 4 dozen bananas is ₹ 180. How many, bananas can be purchased for ₹ 90?
Solution 7:-
Since 1 dozen = 12 units;
So, 4-dozen of bananas = 12 x 4 = 48 bananas;
₹ 180 is the cost of 4 dozen = 4 x 12 = 48 bananas;
₹ 1 is the cost of = (48/180) bananas = 60 bananas;
₹ 90 is the cost of = (0.26 x 90) bananas = 24 bananas
So, the required number of bananas = 24

Question 8 :- The weight, of 72-books is 9-kg. What is the weight of 40-such-books?
Solution 8:-
Weight of 72 books = 9 kg;
Weight of 1 books = (9/72) kg;
Weight of 40 books = [(9/72) x 40] kg = 5 kg;
Hence, the required weight = 5 kg.

Question 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?
Solution 9:-
To cover 594 km, the amount of diesel required = 108 litres;
For 1-km, the required amount of diesel  = (108/594) litres;
To cover 1650 km, the amount of diesel required = [(108/594) x 1650] litres = 300 litres;
So, the required amount of diesel = 300 litres.

Question 10 :- Raju purchases 10-pens, for ₹150 and Manish buys 7 pens, for ₹ 84. Can you say who got the pens-cheaper?
Solution 10:-
For Raju,
Cost of 10 pen = ₹150
Cost of 1 pen = ₹ 150/10 = ₹ 15
For Manish,
Cost of 7 pens = ₹ 84
Cost of 1 pen = ₹ 84/7 = ₹12
Since, ₹ 12 < ₹ 15, So, Manish got the pens cheaper than Raju.

Question 11 :- Anish made 42 runs in 6 overs and Anup made 63 runs in 7 overs. Who made more runs per over?
Solution 11:-

For Anish,

Number of runs made by Anish in 6 overs = 42 runs;
The number of runs made by Anish in 1-over = 42/6 = 7 runs;

For Anup,
Number of runs made by Anup in 7 overs = 63 runs;
The number of runs made by Anup in 1-over = 63/7 = 9 runs;

Since, 9 runs > 7 runs;
So, Anup has made more runs.