In a certain school, the ratio of boys to girls is 5 to 13. If there are 64 more girls than boys, how many boys are there?	Pick one
A) 27  B) 40  C) 45  D) 72  E) 117
The ratio of b to G is 5:13 and the other data point is G are more than boys by 64...   Looking at the ratio we can say that the 8(13-5) extra parts caused this diff of 64. so 1 part corresponds to 64/8= 
<gadget id="calculator">64/8</gadget>
<output>8</output>
8 and so   5 parts correspond to 5*8= 
<gadget id="calculator">5*8</gadget>
<output>40</output>
40.   40
<result>B</result>
In a certain school, the ratio of boys to girls is 5 to 13. If there are 64 more girls than boys, how many boys are there?