OG #32

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OG #32

by diegocuenca » Tue Jul 12, 2011 3:15 pm
sqrt((16)(20) + (8)(32)) =

For some reason I just can't get this one right. I've read the explanation but I can't figure it out. The answer is 24.

sqrt(4x4)(4x5) + (2x4)(4x4x2) =

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by vineeshp » Tue Jul 12, 2011 6:02 pm
If you cant get it that way, just multiply the whole thing out.
It gives you sqrt(320 + 256)
which is sqrt(576) = 24.
Vineesh,
Just telling you what I know and think. I am not the expert. :)

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by MBA.Aspirant » Wed Jul 13, 2011 1:07 am
Another way to do it:

√((16)(20) + (8)(32))

√ (16*20 + 8 * 16 *2)

√ 16 (20 + 8*2)

√ 16 * 36

4 * 6 = 24

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by GMATGuruNY » Wed Jul 13, 2011 2:18 am
diegocuenca wrote:sqrt((16)(20) + (8)(32)) =

For some reason I just can't get this one right. I've read the explanation but I can't figure it out. The answer is 24.

sqrt(4x4)(4x5) + (2x4)(4x4x2) =
Factor out 16:
√(16*20 + 8*32)

=√(16*20 + 8*2*16)

=√(16*(20 + 8*2))

=√(16 * 36)

= 4 * 6

= 24.
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by diegocuenca » Thu Jul 14, 2011 3:48 pm
Awesome, thanks guys.

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by kitg » Thu Jul 14, 2011 7:05 pm
easiest is factor out 16
= sqrt { (16*20) + (16*16))
= sqrt ( 16*(20+16) ) = sqrt (16*36) = 4*6 = 24