A wheel that has 6 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: Select:  A) 4  B) 9  C) 12  D) 21  E) 35
More cogs less revolution,..   so   6:14::x:21   (21*6)/14= 
<gadget id="calculator">(21*6)/14</gadget>
<output>9</output>
9   ANSWER:9
<result>B</result>
A wheel that has 6 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: