Question

A number is incresed by 40% and decrease by 40%.Find the net increase or decrease percent

Answer 1

Let the number be “X”.

40% of X = (40/100)*X = (2/5)*X

Let X1 be the number after 40% increase, X1 = X + (2/5)*X
X1 = X (1 + (2/5))
X1 = X * (7/5)

40% of X1 = (40/100)*X1 = (2/5)* (7/5) * X = (14/25) * X

Let X2 be the number after 40% decrease of X1, X2 = (7/5)*X - (14/25) * X

X2 = (21/25)*X

The net decrease = X - X2 = X - (21/25)*X = (4/25)*X ———> Answer