Exercise 2.1 (Multiplication by lattice algorithm)

Exercise 2.1

1. Multiply the following numbers by using lattice method.

(i) 52 × 49

52 x 49

Answer: 52 x 49 = 2548

(ii) 347 × 5

Answer: 347 x 5 = 1735

(iii) 127 × 7

Answer: 127 x 7 = 889

(v) 65 × 37

Answer: 65 x 37 = 2405

(v) 789 × 4

Answer: 789 x 4 = 3156

(vi) 37 × 29

Answer: 37 x 29 = 1073

2. Multiply the following numbers by using standard method;

(i) 72 × 29

Answer: 72 × 29 = 2088

(ii) 31 × 27

Answer: 31 × 27 = 837

(iii) 93 × 42

Answer: 93 × 42 = 3906

(iv) 124 × 6

Answer: 124 × 6 = 744

(v) 206 × 8

Answer: 206 × 8 = 1648

(vi) 479 × 3

479x3

Answer: 479 × 3 = 1437

3. One box contains 25 apples. How many apples are there in 36 such boxes?

No.of apples in 1 box = 25

No.of apples in 36 boxes= 36 × 25

Answer: There are 900 apples in 36 boxes.

i. There are 28 pages in a daily newspaper. If Ajay buys newspapers for 45 days, how many pages will it contain ?

No. of pages for 1 day = 28

No. of pages for 45 days = 45 × 28

Answer: It will contain 1260 pages

ii. A truck carries 125 bags of rice. If each bag has 9 kg of rice, how much kg of rice will there be in the truck.

Weight of rice in 1 bag = 9 kg

Weight of rice in 125 bags = 125 × 9

Answer: There will be 1125kg of rice in the truck.

iii. If the cost of one chair is ₹ 857. What will be the cost of 6 chairs ?

Cost of 1 chair = ₹ 857

Cost of 6 chairs = 857 × 6

Answer: The cost of 6 chairs will be ₹ 5142.