<PRE><B>Question 251501</B>
The ratio of the number of boys to the number of girls in a room is 5:7.
5:7 is the same as 5x:7x where 5x is the # of boys
and 7x is the number of girls.
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When 24 more boys enter, the ratio is reversed.
# of boys = 5x+24
# of girls is still 7x
Ratio is 7:5
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Equation:
(5x+24)/(7x) = 7/5
Cross-multiply:
25x+120 = 49x
24x = 120
x = 5
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How many girls are in the room?
7x = 35 (# of girls in the room)
Cheers,
Stan H. 

a) 29 b) 32 c) 35 d) 36 e) none of these</PRE>