Question

Two numbers are in the ratio of 7∶ 5. If 6 is added in each the ratio becomes 5∶ 4. The smaller number is:
1. 10
2. 11
3. 12
4. 13

Answer 1

Correct Answer - Option 1 : 10

Calculation:

Let assume that first number is 7x

And second number is 5x

After adding 6 in each number

⇒ First number becomes = 7x + 6

⇒ Second number becomes = 5x + 6

According to the question

⇒ (7x + 6)/ (5x+6) = 5/4

By Cross –Multiplication

⇒ (7x + 6) × 4 = (5x + 6) × 5

⇒ 28x + 24 = 25x + 30

⇒ 3x = 6

⇒ x = 2

So, Greater number = 7 × 2 = 14

And Smaller number is = 5 × 2 =10

∴  The correct option is 1 i.e. 10 .