The sum of squares of three numbers is 280. If the numbers are in the ratio 3:5:6, find the greatest number.
A
8
B
6
C
12
D
18
Correct Option - C
Explaination
Let the numbers be 3x,5x and 6x.
(3x)²+(5x)²+(6x)²=280
9x²+25x²+36x²=280
70x²=280
x²=4
x=2
The greatest number is 6x=12.