The sides of a square region, measured to the
nearest centimeter, are 6 centimeters long. The
least possible value of the actual area of the
square region is
A.36.00 sq cm
B.35.00 sq cm
C.33.75 sq cm
D.30.25 sq cm
E.25.00 sq cm
How to approach such questions ?
PS(Geometry)
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The key information here is measured to the nearest centimeter.rintoo22 wrote:The sides of a square region, measured to the
nearest centimeter, are 6 centimeters long. The
least possible value of the actual area of the
square region is
A.36.00 sq cm
B.35.00 sq cm
C.33.75 sq cm
D.30.25 sq cm
E.25.00 sq cm
How to approach such questions ?
So, the sides do not necessarily have length 6.
In fact 5.5 < (length of 1 side) < 6.5
We want the smallest possible area. This will occur when the side lengths are minimized.
The shortest length of each side is 5.5 cm.
So, the smallest possible area = (5.5)(5.5) = [spoiler]30.25 = D[/spoiler]
Cheers,
Brent
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SIde of square measured to nearest integer = 6
therefore the size could range from 5.5 - 6.4
for area of this square to be the smalles we should consider the smallest number which is 5.5
and if side = 5.5, area of square = 5.5 * 5.5 = 30.25
Hence D
therefore the size could range from 5.5 - 6.4
for area of this square to be the smalles we should consider the smallest number which is 5.5
and if side = 5.5, area of square = 5.5 * 5.5 = 30.25
Hence D
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30.25
Key info is "measured to the nearest cm". Since, we need the least area possible for the square the least side length possible is 5.5. Hence, least area possible is 30.25cm^2
Key info is "measured to the nearest cm". Since, we need the least area possible for the square the least side length possible is 5.5. Hence, least area possible is 30.25cm^2
Best,
Bharat
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Bharat
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As an aside, notice that the question requires us to find (5.5)^2
This is the same as squaring 55 to get 3025 and then moving the decimal over 2 spaces to get 30.25
If anyone is interested, there's a 3-second technique for squaring numbers ending in 5. To learn this technique, watch our free video: https://www.gmatprepnow.com/module/gmat- ... ts?id=1024
Cheers,
Brent
This is the same as squaring 55 to get 3025 and then moving the decimal over 2 spaces to get 30.25
If anyone is interested, there's a 3-second technique for squaring numbers ending in 5. To learn this technique, watch our free video: https://www.gmatprepnow.com/module/gmat- ... ts?id=1024
Cheers,
Brent