A wheel that has 4 cogs is meshed with a larger wheel of 14 cogs. When the smaller wheel has made 21 revolutions, then the number of revolutions mad by the larger wheel is:
Choose the correct choice from the following answers:
A) 49	B) 4	C) 12	D) 6	E) 27
Let the required number of revolutions made by larger wheel be x.   Then, More cogs, Less revolutions (Indirect Proportion)   14 : 4 :: 21 : x 14 * x = 4 x 21   x =	(4 x 21)/14   x = 6.   Answer is 6.
<result>D</result>
A wheel that has 4 cogs is meshed with a larger wheel of 14 cogs. When the smaller wheel has made 21 revolutions, then the number of revolutions mad by the larger wheel is: