The positive numbers are in the ratio 2 : 3 : 4. The sum of their squares is 2349. The average of the first two numbers is:
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 22.5
Calculations:
Let the numbers be 2x, 3x and 4x
According to the question sum of their squares is 2349
⇒ 4x2 + 9x2 + 16x2 = 2349
⇒ 29x2 = 2349
⇒ x2 = 81
⇒ x = 9
Required average = (2x + 3x)/2 = 5x/2
⇒ 45/2 = 22.5