The difference between two positive numbers is 15 and the ratio between them is 7 : 4. Find the sum of the two numbers.

Question: The difference between two positive numbers is 15 and the ratio between them is 7 : 4. Find the sum of the two numbers.

Solution:
Let the two positive numbers be 7x and 4x respectively

According to the question,
7x - 4x = 15
⇒ 3x = 15
⇒ x = 5

Then numbers are 7 × 5 = 35 and 4 × 5 = 20
So, sum of numbers = 35 + 20 = 55