You buy a new cell phone for $79.99. The sales tax on the phone is 7%. What is the total cost for the cell phone?

Sales tax is 0.07 so the combined price of the cell phone and the tax would be 1.07 of $79.99. So multiply 1.07 by 79.99:

79.99 * 1.07 ≈ 85.59

The cell phone will cost $85.59.

It is approximate because the actual value of 1.07 * 79.99 is 85.5893 but I rounded up.

79.99 x 0.07 = 5.60

79.99 + 5.60 = 85.59

$85.59