The best way to solve this is to put it into a proportion:
[tex] \frac{x}{84} = \frac{ \frac{1}{4} }{ \frac{3}{4} } [/tex]
So you cross multiply to get:
[tex]21= \frac{3}{4} x[/tex] (the 21 is from [tex] \frac{1}{4} [/tex]•84)
Then multiply by [tex] \frac{4}{3} [/tex]
And you get $28, so the reduced price would be $28.
