Question

1,250 an 15% sale an 6.5 sales tax

Answer 1

Given:
price = 1,250
sales discount = 15%
sales tax = 6.5%

The problem is unclear whether the price is the original price or the discounted price. I am assuming that the price is the original price.

Original price times sales discount rate is the value of sales discount
1,250 x 15% = 187.50

Original price less the value of sales discount is the discounted price.
1,250 - 187.50 = 1,062.50

Discounted price times sales tax rate is the value of the sales tax
1,062.50 x 6.5% = 69.06 

Discounted price plus sales tax is the total cost of the purchase
1,062.50 + 69.06 = 1,131.56