The sales tax rate is 4%. If the sales tax on a 10-speed bicycle is $6, what is the purchase price?

So percent is parts out of 100

4%=4/100=1/25

tax=6

6=1/25 of original price

solve for 100/100

6=1/25 of original price

multiply both sides by 25

150=original price

purchase price=150

but if added tax it is 156

so purchased for $156