Pihu has to do a multiplication. Instead of taking 32 as one of the multipliers, he took 23. As a result the product went

Pihu has to do a multiplication. Instead of taking 32 as one of the multipliers, he took 23. As a result the product went down by 72. What is the sum of the digits of the new product?

a) 15

b) 14

c) 13

d) 12

Sol:

Number = y

Decrease in number = 32y – 23y

= 9y

9y = 72

y = 8