The ratio between the perimeter and the breadth of a rectangle is 5 : 1. If the area of the rectangle is 216 sq. cm, what is the length of the rectangle?
A) 16
B) 18
C) 20
D) 22
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Let the length be L and breadth be b
Perimeter/ Breadth = 5/1
2(L + b)/ b = 5/1
Cross multiplying, we get:
2(L + b) = 5b
2L + 2b = 5b
2L = 5b-2b
2L = 3b
b = 2L /3
Area =216
L * b = 216
Substituting for b:
L * 2L/3 = 216
2(L^2)/3 = 216
L^2 = 324
L = 18 cm
The answer is (B) 18
Perimeter/ Breadth = 5/1
2(L + b)/ b = 5/1
Cross multiplying, we get:
2(L + b) = 5b
2L + 2b = 5b
2L = 5b-2b
2L = 3b
b = 2L /3
Area =216
L * b = 216
Substituting for b:
L * 2L/3 = 216
2(L^2)/3 = 216
L^2 = 324
L = 18 cm
The answer is (B) 18
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