Question

12. The length of a rectangular plot is increased by 25% while its breadth is decreased
by 25%. As a result, the area of the plot will
(a) Remain unchanged
(b) Increase by 6.25%
(c) Decrease by 6.25%
(d) Decrease by 12.5%​

Answer 1

Answer:

(c) Decrease by 6.25%

Step-by-step explanation:

Let L be the length of the original rectangle

Let B be the breadth of the original rectangle.

Area (A) = L * B

Now, length is increased by 25 per cent. Hence,

New length = 1.25*L

Breadth is decreased by 25 per cent. Hence,

New breadth = 0.75*B

Area of new rectangle = 1.25*L*0.75*B

                                      = 0.9375*(L*B)

Hence, new area is 0.9375 of the old area.

This means that the new area = 93.75% of the original area

This also means that new area = (100-93.75)% lower than the original area.

                                                    = 6.25% lower than original area