Here's one approach:
First recognize that √184,513 ≈ √180,000
Then we'll use the fact that √(xy) = (√x)(√y)
So, √180,000 = √[(18)(10,000)]
= (√18)(√10,000)
= (4.something)(100)
= some value between 400 and 500
= D
How do we know that √18 = 4.something?
Well, √16 = 4 and √25 = 5, so √18 must be BETWEEN 4 and 5
Cheers,
Brent
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Here's another approach:
√160,000 = 400
√250,000 = 500
So, √184,513 must be BETWEEN 400 and 500
Answer: D
Cheers,
Brent
√160,000 = 400
√250,000 = 500
So, √184,513 must be BETWEEN 400 and 500
Answer: D
Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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theCodeToGMAT
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Another approach:
In answer choices we see x00 .. so (x00)^2 = x0000.. compare this with question..
x = 18
==> sqrt(18) ==> between 4 & 5..as 4^2 = 16 & 5^2 = 25
So, 400 and 500
[spoiler]{D}[/spoiler]
In answer choices we see x00 .. so (x00)^2 = x0000.. compare this with question..
x = 18
==> sqrt(18) ==> between 4 & 5..as 4^2 = 16 & 5^2 = 25
So, 400 and 500
[spoiler]{D}[/spoiler]
R A H U L
