The length, breadth and height of a cuboidal box are in the ratio 4 : 3 : 2 and its total surface area is 1300 sq cm. Find the length of the box (in cm).
Class 8Surface Area of Cuboid and CubeMensuration
A22
B20
C18
D40
Step-by-Step Solution
Let l=4x,b=3x,h=2x. TSA = 2(12x2+6x2+8x2)=2×26x2=52x2=1300, so x2=25,x=5. Length = 4x=20 cm.
Answer: B) 20
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