This is probably simple but I'm just missing something...the solution to an MGMAT question states the following:
"
6/1 * 9/28 * 7/9 * 1/2 =
6/8 = 3/4
Notice that if you avoid computation until the very end, some of the numerators and denominators cancel each other out."
How did they avoid the computation? What numerators and denominators canceled out? Clearly I'm missing something and doing time costly math.
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jangelo1989
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Brent@GMATPrepNow
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Let's simplify in parts
(6/1)(9/28)(7/9)(1/2)
(6/1)(9/28)(7/9)(1/2) = (6/1)(1/28)(7/1)(1/2) [9's cancel out]
(6/1)(1/28)(7/1)(1/2)
(6/1)(1/28)(7/1)(1/2) = (6/1)(1/4)(1/1)(1/2) [7/28 simplifies to 1/4]
(6/1)(1/4)(1/1)(1/2) = 6/8 [multiply numerators and denominators]
= 3/4 [simplify]
Cheers,
Brent
(6/1)(9/28)(7/9)(1/2)
(6/1)(9/28)(7/9)(1/2) = (6/1)(1/28)(7/1)(1/2) [9's cancel out]
(6/1)(1/28)(7/1)(1/2)
(6/1)(1/28)(7/1)(1/2) = (6/1)(1/4)(1/1)(1/2) [7/28 simplifies to 1/4]
(6/1)(1/4)(1/1)(1/2) = 6/8 [multiply numerators and denominators]
= 3/4 [simplify]
Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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jangelo1989
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