NCERT Solutions Class 6th Maths Chapter – 2 Whole Numbers Exercise – 2.2

Question 1. Find the sum by suitable rearrangement:

(a) 837 + 208 + 363
Solution: Given 837 + 208 + 363
= (837 + 363) + 208
= 1200 + 208
= 1408

(b) 1962 + 453,+ 1538 + 647
Solution: Given 1962 + 453 + 1538 + 647
= (1962 + 1538) + (453 + 647)
= 3500 + 1100
= 4600

Question 2. Find the product by suitable rearrangement:

(а) 2 x 1768 x 50
Solution: Given 2 × 1768 × 50
= 2 × 50 × 1768
= 100 × 1768
= 176800

(b) 4 x 166 x 25
Solution: Given 4 × 166 × 25
= 4 × 25 × 166
= 100 × 166
= 16600

(c) 8 x 291 x 125
Solution: Given 8 × 291 × 125
= 8 × 125 × 291
= 1000 × 291
= 291000

(d) 625 x 279 x 16
Solution: Given 625 × 279 × 16
= 625 × 16 × 279
= 10000 × 279
= 2790000

(e) 285 x 5 x 60
Solution: Given 285 × 5 × 60
= 285 × 300
= 85500

(f) 125 x 40 x 8 x 25
Solution: Given 125 × 40 × 8 × 25
= 125 × 8 × 40 × 25
= 1000 × 1000
= 1000000

Question 3. Find the value of the following:

(а) 297 x 17 + 297 x 3
Solution: Given 297 × 17 + 297 × 3
= 297 × (17 + 3)
= 297 × 20
= 5940

(b) 54279 x 92 + 8 x 54279
Solution: Given 54279 × 92 + 8 × 54279
= 54279 × 92 + 54279 × 8
= 54279 × (92 + 8)
= 54279 × 100
= 5427900

(c) 81265 x 169 – 81265 x 69
Solution: Given 81265 × 169 – 81265 × 69
= 81265 × (169 – 69)
= 81265 × 100
= 8126500

(d) 3845 x 5 x 782 + 769 x 25 x 218
Solution: Given 3845 × 5 × 782 + 769 × 25 × 218
= 3845 × 5 × 782 + 769 × 5 × 5 × 218
= 3845 × 5 × 782 + 3845 × 5 × 218
= 3845 × 5 × (782 + 218)
= 19225 × 1000
= 19225000

Question 4. Find the product using suitable properties.

(a) 738 x 103
Solution: 738 x 103
= 738 x (100 + 3)
= 738 x 100 + 738 x 3 [Using distributive property]
= 73800 + 2214
= 76014

(b) 854 x 102
Solution: 854 x 102
= 854 x (100 + 2)
= 854 x 100 + 854 x 2 [Using distributive property]
= 85400 + 1708
= 87108

(c) 258 x 1008
Solution: 258 x 1008
= 258 x (1000 + 8)
= 258 x 1000 + 258 x 8 [Using distributive property]
= 258000 + 2064
= 260064

(d) 1005 x 168
Solution: 1005 x 168
= (1000 + 5) x 168
= 1000 x 168 + 5 x 168 [Using distributive property]
= 168000 + 840
= 168840

Question 5. A taxi driver filled his car petrol tank with 40 litres of petrol on Monday. The next day, he filled the tank with 50 litres of petrol. If the petrol cost ₹44 per litre, how much did he spend in all on petrol?

Solution: Petrol filled on Monday = 40 litres
Cost of petrol = Rs 44 per litre
Petrol filled on Tuesday = 500 litre
Cost of petrol = Rs 44 per litre
∴ Total money spent in all
= Rs (40 x 44 + 50 x 44)
= Rs (40 + 50) x 44 = Rs 90 x 44 = Rs 3960

Question 6.A vendor supplies 32 litres of milk to a hotel in the morning and 68 litres of milk in the evening. If the milk costs ₹45 per litre, how much money is due to the vendor per day?

Solution: The quantity of milk supplied in the morning = 32 litres
The quantity of milk supplied in the evening = 68 litres
Cost of milk per litre = Rs 45
Thus, total cost of milk per day = 45 × (32 + 68)
= 45 × 100
= Rs 4500

Solution: