Joana spent $145 on groceries and after tax the final amount was $156.6. What was the tax rate

8%

Step-by-step explanation:

Tax equals the original amount times the tax rate

We can find the tax by taking the amount he paid minus the original amount

tax = 156.6 - 145

tax = 11.6

tax = original amount * tax rate

11.6 = 145 * tax rate

Divide each side by 145

11.6/145 = 145/145 * tax rate

.08 = tax rate

To change this to percent, multiply by 100%

.08*100% = 8%