Question

The cost of a chocolate is Rs (x + y) and Rohit bought (x + y) chocolates. Find the total amount paid by him in terms of x. If x = 10, find the amount paid by him.

Answer 1

Given, cost of a chocolate = ₹ (x + 4)

Rohit bought (x + 4) chocolates

∴ The cost of (x + 4) chocolates = Cost of one chocolates × Number of chocolates

= (x + 4)(x + 4)

= (x + 4)²  ...[∵ (a + b)² = a² + 2ab + b²]

= x² + 8x + 16

∴ The total amount paid by Rohit = ₹ (x² + 8x + 16)

Now, If x = 10.

Then, the amount paid by Rohit = 10² + 8 × 10 + 16

= 100 + 80 + 16

= ₹ 196