Question

marta's checkbook shows that she wrote a check for $987 for building materials. what was the price of materials if sales if sales tax is 5%

Answer 1

you know that the prices of the materials plus the tax is $987 so if you put P as the price of the materials you know
\[p(1.05)=\$987\] solve for P via
\[P=\$987\div 1.05\]