In a certain school, the ratio of boys to girls is 5 to 13. If there are 160 more girls than boys, how many boys are there? Pick
A) 100  B) 36  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 160...   Looking at the ratio we can say that the 8(13-5) extra parts caused this diff of 160. so 1 part corresponds to 160/8= 
<gadget id="calculator">160/8</gadget>
<output>20</output>
20 and so   5 parts correspond to 5*10= 100.   100
<result>A</result>
In a certain school, the ratio of boys to girls is 5 to 13. If there are 160 more girls than boys, how many boys are there?