Abe looked at his reciept and noted that the total before the discount was $75 but he paid only $56.25. Barb's total was $52 but she paid only $31.20.

Question

Story problems are my worst nightmare.  College Mathematics for Educators.

Answer 1

you don't state what it's asking for, but I'll assume they want what the percent discount is.

 

Let D = discount (as a decimal fraction 0-1)   where PCT = 100*fraction  

 

in general,    PRICE -  PRICE*D =  final price

rewritten       PRICE*(1 - D)      =  final price

 

so Solve for D:                     D = 1 -  (final price/PRICE)

the PCT = D*100

 

Abe's Total before discount: $75 and the final price was $56.25

so D = 1 - (56.25/75) = 0.25 ........... SO PCT = 100*0.25 = 25%    (Abe's discount)

 

 

Barb's Total before discount: $52 and the final price was $31.20

so D = 1 - (31.20/52) = 0.40 ............SO PCT = 100*0.40 = 40%  (Barb's discount)