Answer: 112
Step-by-step explanation:
you have a price let's say 400$. 25% of that price you don't have to pay. 25% of that is (25/100)*400=100. A quarter of it. So you don't have to pay a 100 bucks. it only costs you 300.
So if the price was unkown, but you know that 3 quarters of it is 84, then you equation is x-(x*0,25)=84.
84+0,25x=x ///-0,25x -> you take away this from both sides
84=1x-0,25x
84=0,75x
x=112
112*0,25=28
112-28=84