Convert the percent into a decimal by multiplying by 0.01: the percent in this problem is 6.5%, so when you multiply by 0.01, you get 0.065
Multiply the price by your new decimal: in this case, that would mean to multiply 1580 by 0.065, which gives you 102.7. <u>Keep in mind that this is just the tax, not your final answer.</u>
Add the tax you just calculated to the original price: add 102.7 to 1580 to get 1,682.7. That is your final answer.
I think the answer to the expression would be D. (10 - 2) x 4 because (10 - 2) would be multiplied 4 times, which means it would be four times greater. I hope this made sense and also helped you in some way.