Kaplan square Lawn

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Kaplan square Lawn

by singhsa » Tue Sep 21, 2010 5:01 pm
If a square lawn has an area a, what is the length of a pathway that leads from one corner of the lawn directly to the exact center of the lawn?

a. rt(2a)/2
b. rt(2a)
c. a rt(2)/2
d. rt(a)
e. a


Here, let the sides of the square be s. So, area=s^2=a.

diagonal = s rt(2)= rt(a) rt(2)=rt(2a). What am I missing here??

OA - A
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by Rahul@gurome » Tue Sep 21, 2010 6:30 pm
If a square lawn has an area a, what is the length of a pathway that leads from one corner of the lawn directly to the exact center of the lawn?

a. rt(2a)/2
b. rt(2a)
c. a rt(2)/2
d. rt(a)
e. a

Solution:
If the area of square lawn is "a", side is sqrt(a).
So diagonal is sqrt(2)*(sqrt(a)).
Or Length of pathway that leads from corner to centre is [sqrt(2)*(sqrt(a))]/2 = sqrt(2*a)/2. Here we use the formula that (m^x)*(n^x) = (mn)^x. For this problem m = 2, n = a and x = 1/2.

The correct answer is (A).
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by singhsa » Wed Sep 22, 2010 5:13 pm
Rahul@gurome wrote:If a square lawn has an area a, what is the length of a pathway that leads from one corner of the lawn directly to the exact center of the lawn?

a. rt(2a)/2
b. rt(2a)
c. a rt(2)/2
d. rt(a)
e. a

Solution:
If the area of square lawn is "a", side is sqrt(a).
So diagonal is sqrt(2)*(sqrt(a)).
Or Length of pathway that leads from corner to centre is [sqrt(2)*(sqrt(a))]/2 = sqrt(2*a)/2. Here we use the formula that (m^x)*(n^x) = (mn)^x. For this problem m = 2, n = a and x = 1/2.

The correct answer is (A).

Aww man. The question is asking for the distance from the corner to the CENTRE. Silly mistake there.

Thanks Rahul !!!