The fourth proportional to 5, 8, 15 is:

A. 18

B. 24

C. 19

D. 20

Answer: Option B

Solution(By Examveda Team)

$$\eqalign{ & {\text{Let}}\,{\text{the}}\,{\text{fourth}}\,{\text{proportional}}\,{\text{to}}\,5,\,8,\,15\,{\text{be}}\,x \cr & {\text{Then}},\,5:8:15:x \cr & \Rightarrow 5x = {8 \times 15} \cr & x = \frac{{ {8 \times 15} }}{5} = 24 \cr} $$