Two numbers are in the ratio 3 : 5. If 4 is subtracted from each of these two numbers, the new numbers then are in the ratio 4 : 7. Find the smaller of the two original numbers.

36

Here,

A : B

3 : 5

Then 4 is subtracted from each of these two numbers, the new numbers then are in the ratio

A : B

4 : 7

⇒ To compare both ratio we multiply initial ratio with 3 and final with 2

⇒ (3 : 5) x 3 = 9 : 15         (4 : 7) x 2 = 8 : 14

⇒ (15 - 14) units = 4

⇒ 1 unit = 4

⇒ The smaller of the two original numbers = 9 x 4 = 36.