7.25% sales tax on a $89.99 cable modem

Sales tax is: $6.52

Step-by-step explanation:

You must multiply $89.99 by 0.0725 (this is how you find sales tax, moves decimal two places to the left)

When you multiply that, you get 6.524275, and you must round to 6.52. This is your sales tax.

The total price (with sales tax included) is: $96.51

amount of apples bought =$ 2.6

amount of peaches bought =$ 1.475

amount given by you to cashier= $ 20

amount received by me= amount given by you to cashier -   [amount of apples bought +amount of peaches bought]

                                        = 20   - [1.475 + 2.6]

                                        = 20 -   [ 4.075]

                                        =   $15.925

so, change received by me = $15.925