Question

a number decreased by 20% and again incresed by 20% what was the percentage decrease

Answer 1

net percentage change=
= -20+20-(20×20)/100
=0-400/100
= -4 % decrease

Answer 2

Let Number be=100

It decreased by 20%
Now number become=100-(100×20%)
=80

Now 80 Incresed by =20%
Now number become=80+(80×20%)
=96

Number decrease=100-96
=4
So decrease percent=4%

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