Arithmetic Ability
Area

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Q.

The diagonal of a rectangle is 41−−√ cm and its area is 20 sq. cm. The perimeter of the rectangle must be:

View Answer

Correct choice: A

Explanation:

(l2+b2)−−−−−−−√=41−−√ (or) l2+b2=41 Also, lb=20 (l+b)2=l2+b2+2lb = 41 + 40 = 81 (l + b) = 9. Perimeter = 2(l + b) = 18 cm.
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