If the third proportion of 3 and x is 27 and the third proportion of 2 and y is 8, then find x : y.
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 9 : 4.
The third proportion of 3 and x is 27
= 3 : x : 27
= 3/x = x/27
x2 = 81
x = 9
The third proportion of 2 and y is 8
2 : y : 8
= 2/y = y/8
y2 = 16
y = 4
So, the ratio of x : y = 9 : 4