math
posted by Brooke .
Ben purchased 5 shirts for $12.95 each. How much sales tax will he pay if the tax rate is 6%?

Multiply the total sale by 0.06 (=6%).
Total sale = 5*12.95=64.92
Sales Tax = $64.92*0.06=$3.90 
You actually multiplied wrong, because 5*12.95= 64.75 not 64.92.
The answer I got from the structure you wrote was $3.89
Thanks though! It really helped! 
actually you are both wrong he would pay exactly 0.777 cents in sales tax which rounds off to 0.78 cents in sales tax

for one shirt

so brooke is right the total sales tax is $3.89

Dustin  the problem asks for the sales tax on five shirts.
Brooke is right. The sales tax on all five shirts is $3.89. I'm glad you checked the tutor's math. We all make mistakes. 
Thank you all for the corrections.
As Ms Sue said, I am glad you check the math.
Remember that you should always check the tutor's math, not only for accuracy, but also to verify that you have understood how it is done.
Sorry for the bad multiplication. It was a moment of inattention of my mental arithmetic.