darry and nay eat dinner at a restaurant with 6% sales tax. They leave an 18% tip on the pre tax amount of the bill. If they paid a total of 37.20, what was their pre tax bill?
pre tax = 1.18 p
1.18 p * 1.06 = 37.20
so
p = 37.20 / (1.18*1.06)
1.18 p * 1.06 = 37.20
so
p = 37.20 / (1.18*1.06)