SOLUTION: hello I am helping my 7th grader with a math project but I have forgotten how to do this problem: if he is buying a t shirt for $5 and he sells it for $12 how do we equate the per

Algebra ->  Percentages: Solvers, Trainers, Word Problems and pie charts -> SOLUTION: hello I am helping my 7th grader with a math project but I have forgotten how to do this problem: if he is buying a t shirt for $5 and he sells it for $12 how do we equate the per      Log On


   

Question 831795: hello I am helping my 7th grader with a math project but I have forgotten how to do this problem: if he is buying a t shirt for $5 and he sells it for $12 how do we equate the percentage of his markup? please and thank you very much
Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
let x be the percent markup, then we have
5 + 5*(x/100) = 12
subtract 5 from both sides of =
5*(x/100) = 7
multiply both sides of = by 100
5x = 700
x = 140
the markup is 140%