Mathematics
posted by Jennifer on .
Tito Sanchez receives a weekly salary of $400. he also receives a 6% commission on the total dollar amount of all sales he makes. What must his total sales be in a week if he is to make a total of $790?

if sales = x, then salary s is given by
s = 400 + .06x
If s=790, then
790 = 400 + .06x
390 = .06x
x = 6500 
Petsmart has sale offering 10% off of all pet supplies. If Amanda Miller spent 15.72$ on pet supplies before tax, what was the price of the pet supplies she purchased before discount?