Question

A pineapple costs rs. 7. A watermelon cots rs. 5. X spends rs. 38 on these fruits. The number of pineapples purchased is _______.

• A. 2
• B. 3
• C. 4
• D. Data inadequate

Answer 1

The correct option is C 4

Let the number of pineapple and watermelon be x and y
Then 7x+5y=38 (given cost of pineapple and watermelon is Rs 7and Rs 5
Or 5y=38-7x
Or $y=\frac{38-7x}{5}$
clearly y is whole number only when (38-7x) is divisible by 5
This happens when x=4