NCERT Solutions for Class 6 Maths Chapter 12 Ratios and Proportions Ex 12.3

NCERT Solutions for Class 6 Maths Chapter 12 Ratios and Proportions Ex 12.3 are the part of NCERT Solutions for Class 6 Maths (Rationalised Contents). Here you can find the NCERT Solutions for Class 6 Maths Chapter 12 Ratios and Proportions Ex 12.3.

NCERT Solutions for Class 6 Maths Chapter 12 Ratios and Proportions Ex 12.3 (Rationalised Contents)

Ex 12.3 Class 6 Maths Question 1.

If the cost of 7 m of cloth is ₹ 1470, find the cost of 5 m of cloth.

Solution:
Using unitary method, we have

Cost of 7 m of cloth = ₹ 1470
Cost of 1 m of cloth = ₹ 1470/7 = ₹ 210
Cost of 5 m of cloth = ₹(210 × 5) = ₹ 1050
Thus, the cost of 5 m of cloth is ₹ 1050.

Ex 12.3 Class 6 Maths Question 2.

Ekta earns ₹ 3000 in 10 days. How much will she earn in 30 days?

Solution:
Using unitary method, we have

In 10 days, Ekta earns ₹ 3000.
In 1 day, Ekta will earn ₹ 3000/10 = ₹ 300
In 30 days, Ekta will earn ₹300 × 30 = ₹ 9000
Thus, the money earned by Ekta in 30 days is ₹ 9000.

Ex 12.3 Class 6 Maths Question 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.

Solution:
Using unitary method, we have

In last 3 days, the rain falls 276 mm.
In 1 day, the rain falls = 276/3 mm = 92 mm
In 7 days, the rain will fall = 92 × 7 mm = 644 mm
Thus, the amount of rain fall in a full week is 644 mm.

Ex 12.3 Class 6 Maths 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:
(a) Cost of 5 kg of wheat = ₹ 91.50
Cost of 1 kg of wheat = ₹ 91.50/5 = ₹ 18.30
Cost of 8 kg of wheat = ₹ (18.30 × 8)
= ₹ 146.40
Thus, the required cost of 8 kg of wheat is ₹ 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 = 183 × 5/91.50 kg

= 915/91.5 = 10 kg
Thus, the required quantity of wheat purchased is 10 kg.

Ex 12.3 Class 6 Maths 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:
In last 30 days, the temperature dropped = 15° C
In last 1 day, the temperature dropped = 15/30° C = ½ ° C
In nest 10 days, the temperature will drop = ½ × 10° C = 5° C
Thus, the required drop in temperature in next 10 days will be 5° C.

Ex 12.3 Class 6 Maths Question 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?

Solution:
Amount of rent paid in 3 months = ₹ 15000
Amount of rent paid in 1 month = ₹ 15000/3 = ₹ 5000
Amount of rent paid in 12 months = ₹ (5000 × 12)
= ₹ 60,000
Thus, the required amount of rent paid in 1 year is ₹ 60,000.

Ex 12.3 Class 6 Maths Question 7.

Cost of 4 dozen bananas is ₹ 180. How many bananas can be purchased for ₹ 90?

Solution:
∵ 1 dozen = 12 units
∴ 4 dozen of bananas = 12 × 4 = 48 bananas
₹ 180 is the cost of 48 bananas.
₹ 1 is the cost of 48/180 bananas.
₹ 90 is the cost of = 90 × 48/180 bananas
= 24 bananas
Thus, the required number of bananas is 24.

Ex 12.3 Class 6 Maths Question 8.

The weight of 72 books is 9 kg. What is the weight of 40 such books?

Solution:
The weight of 72 books = 9 kg
The weight of 1 book = 9/72 kg
The weight of 40 books = 40 × 9/72 kg = 5 kg
Thus, the weight of 40 books is 5 kg.

Ex 12.3 Class 6 Maths 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:
To cover 594 km, the amount of diesel required = 108 litres
To cover 1 km, the amount of diesel required = 108/594 litres
To cover 1650 km, the amount of diesel required = 1650 × 108/594 litres = 300 litres
Thus, the required amount of diesel is 300 litres.

Ex 12.3 Class 6 Maths Question 10.

Raju purchases 10 pens for ₹150 and Manish buys 7 pens for ₹ 84. Can you say who got the pens cheaper?

Solution:
For Raju,
Cost of 10 pens = ₹150
Cost of 1 pen = ₹ 150/10 = ₹ 15
For Manish,
Cost of 7 pens = ₹ 84
Cost of 1 pen = ₹ 84/7 = ₹12
∴ ₹ 12 < ₹ 15

Thus, Manish got the pens in cheaper price than Raju.

Ex 12.3 Class 6 Maths Question 11.

Anish made 42 runs in 6 overs and Anup made 63 runs in 7 overs. Who made more runs per over?

Solution:
Number of runs scored by Anish in 6 overs = 42
Number of runs scored by him in 1 over = 42/6 = 7 runs
Number of runs scored by Anup in 7 overs = 63
Number of runs scored by him in 1 over = 63/7 = 9 runs
∴ 9 runs > 7 runs.
Thus, Anup has made more runs per over.