The length of a class room floor exceeds its breadth by 25 m. The area of the floor remains unchanged when the length is decreased by 10 m but the breadth is increased by 8 m. The area of the floor is

The length of a class room floor exceeds its breadth by 25 m. The area of the floor remains unchanged when the length is decreased by 10 m but the breadth is increased by 8 m. The area of the floor is Correct Answer 5100 sq.m

Let the breadth of floor be 'b' m.

Then, length of the floor is 'l = (b + 25)'

Area of the rectangular floor = l x b = (b + 25) × b

According to the question,

(b + 15) (b + 8) = (b + 25) × b

b2 + 8b + 15b + 120 = b2 + 25b

2b = 120

b = 60 m.

l = b + 25 = 60 + 25 = 85 m.

 

Area of the floor = 85 × 60 = 5100 sq.m.

Bissoy MCQ

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A question and two statements numbered I and II are given below it. You have to decide whether the data provided in the statements are sufficient to answer the question. A six storey building consisting of an unoccupied ground floor and above ground floor is floor no. 1, so on and topmost floor is no. 5. Different people lives in building viz. I, J, K, l and M. Who lives on the third floor? I. K lives on an even numbered floor. I lives immediately above L. J lives immediately above I. M does not live on the topmost floor. II. L lives on an odd numbered floor. I and J are immediate neighbours of each other. Similarly, K and M are immediate neighbours of each other. K does not live on an odd numbered floor.