Area Problems
A rectangle has 15 cm as its length and 150 cm 2 as its area .Its area is increased to 1 1 / 3 times the original area by increasing only its length . Its new perimeter is?
Diagonal of square = ?2a [a = side]4?2 = ?2 a a = 4 cmNow, area of square = a2 = (42) = 16Side of a square whose area is 2 x 16.a12 = 32 ? a1 = ?32 ?a14?2Now, diagonal of new square = ?2a = ?2x 4 ?2 = 8 cm
Let length of the rectangular field = 7k m and breadth of the rectangular field = 2k mAccording to the question,Area of a rectangular field = Length x Breadth? 3584 = 7k x 2k ? 14 x k2 = 3584 ? k2 = 3584/14 = 256? k2 = 256 = 16 m? Length of rectangular field = 7k = 7 x 16 = 112 mAnd breadth of rectangular field = 2 x 16 = 32 m? Perimeter of rectangle = 2(Length x Breadth)= 2(112 + 32) = 2 x 144 = 288 m
Let l = 4k and b = 9kArea of rectangle = l x b144 = 4k x 9k ? k2 = 144/36 ? k2 = 4? k = 2? l = 8 cm and b = 18 cmPerimeter of rectangle = 2(l + b)= 2(8 + 18)= 2 x 26= 52 cm
EXAMIANS