Susan finds that she spends her free time during summer vacation between swimming, reading, and hanging out with friends in a ratio of 1:4:10. How many hours did she spend reading if she hung out with her friends for 20 hours? Choose one.
A) 2  B) 4  C) 5  D) 8  E) 10
The ratio is 1 hour swimming: 4 hours reading: 10 hours hanging out with friends.   Divide 20 by 10 to find 1 "part" of the ratio.   20/10= 
<gadget id="calculator">20/10</gadget>
<output>2</output>
2   Multiply this by 4 to find the hours spent reading.   2*4= 
<gadget id="calculator">2*4</gadget>
<output>8</output>
8   The answer is 8.
<result>D</result>
Susan finds that she spends her free time during summer vacation between swimming, reading, and hanging out with friends in a ratio of 1:4:10. How many hours did she spend reading if she hung out with her friends for 20 hours?