A and B are two multiples of 14, and Q is the set of consecutive integers between A and B, inclusive. If Q contains 11 multiples of 14, how many multiples of 7 are there in Q?
Answers: A) 19 B) 20 C) 21 D) 22 E) 23
Halfway between the multiples of 14, there will be another multiple of 7.   The total number of multiples of 7 is  11+10= 
<gadget id="calculator"> 11+10</gadget>
<output>21</output>
21.   The answer is 21.
<result>C</result>
A and B are two multiples of 14, and Q is the set of consecutive integers between A and B, inclusive. If Q contains 11 multiples of 14, how many multiples of 7 are there in Q?