The rectangular field is increased by 50 % and its breadth is decrease

1.	The rectangular field is increased by 50 % and its breadth is decreased by 50 % to form a new rectangular field.find the percentage change in the area of the field.
Answer» Let the length of rectangle be aAnd width of rectangle be bArea = ab Now, New length = a + 50% of a= a+ 50a/100= a+a/2= 3a/2 New width = b - 50% of b= b - b/2= b/2 New Area = 3a/2 * b/2= 3ab/4 Decrease in Area = ab - 3ab/4= ab/4 % of Decrease in Area = [(ab/4) * 100] / ab= 100 / 4= 25 %

The rectangular field is increased by 50 % and its breadth is decreased by 50 % to form a new rectangular field.find the percentage change in the area of the field.

Answer»

Let the length of rectangle be aAnd width of rectangle be bArea = ab

Now,

New length = a + 50% of a= a+ 50a/100= a+a/2= 3a/2

New width = b - 50% of b= b - b/2= b/2

New Area = 3a/2 * b/2= 3ab/4

Decrease in Area = ab - 3ab/4= ab/4

% of Decrease in Area = [(ab/4) * 100] / ab= 100 / 4= 25 %