A room contains 160 people, 15 percent of whom are women. A group of people, 30 percent of whom are women, leaves the room. Of the people remaining in the room, 10 percent are women. How many people left the room?
Answers:	A) 10	B) 20	C) 40	D) 60	E) 80
Say group of x people left the room.   # of women in the room was 0.15*160= 
<gadget id="calculator">0.15*160</gadget>
<output>24</output>
24;   # of women in the group that left 0.3x;   # of women in the room after the group left it is 0.1(160-x);   So, 24-0.3x= 0.1(160-x) --&gt; x=40.   Answer: 40.
<result>C</result>
A room contains 160 people, 15 percent of whom are women. A group of people, 30 percent of whom are women, leaves the room. Of the people remaining in the room, 10 percent are women. How many people left the room?