20
Q:
A) 4 | B) 9 |
C) 12 | D) 49 |
Answer: B) 9
Explanation:
Explanation:
Let the required number of revolutions made by larger wheel be x.
Then, More cogs, Less revolutions (Indirect Proportion)
14 : 6 :: 21 : x => 14 x x = 6 x 21
x=6*21/14 => x=9