Question

Given three numbers, first is twice the second and is half of the third. If the average of three numbers is 56, then difference of first and third number is
1. 12
2. 24
3. 36
4. 48

Answer 1

Correct Answer - Option 4 : 48

Given:

First number is twice the second means second number is half of first

And First number is half of the third means third number is twice of first

Average of first 3 numbers = 56

Calculation:

Let the first number be x

Second number = x/2

Third number = 2x

Average of three number x, x/2 and 2x = 56

⇒ (x + x/2 + 2x)/3 = 56

⇒ (7x/2)/3 = 56

⇒ x = 336/7 = 48

Difference between first and third number = 2x - x = x

∴ Difference between first and third number = 48