Ten tuning forks are arranged in increasing order of frequency is such a way that any two nearest tuning forks produce `4 beast//sec`. The highest freqeuncy is twice of the lowest. Possible highest and the lowest frequencies are

Options

A. 80 and 40
B. 100 and 50
C. 44 and 32
D. 72 and 36

Answer

D

Explanation

In n is frequency of first fork, then frequency of the last (10th fork) `= n + 4(10 -1) = 2n`
`:. N = 36 and 2n = 72`