What is the ratio of the mean proportional between 1.6 and 3.6 and the third proportional of 5 and 8?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 3 : 16.
Formula Used:
For 2 numbers a,b,
Mean proportion = √ab
Third proportion = b²/a
Calculation:
Mean proportion of 1.6 and 3.6 = √(1.6 × 3.6)
⇒ 2.4
The third proportion of 5 and 8,
⇒ 64/5
Required ratio = (2.4 : 64/5) = 12 : 64
⇒ 3 : 16
The required answer is 3 : 16.