Problem Solving (PS) | Re: A part-time employee whose hourly wage was increased by 25

Hi Let the number of hours be in 1 week x
and his hourly wage be y
then his total weekly income will be =x*y
His hourly wage increased by 25 % then his new hourly wage will be =1.25y
But he reduces his number of hours worked to maintain same total wage , therefore we have ,
Let a% be the actual decrease in y
Then
1.25axy=xy
a=1/1.25=4/5 =80% so hours are by reduced by 20%

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