The total cost of the dinner meals taken by Arif and Keisha = $13.75
Percentage of tax that need to be given = 5%
Then
Amount of tax that needs to be given = (5/100) * 13.75 dollars
                              = 13.75/20 dollars
                              = 0.687 dollars
                              = 0.69 dollars
So
The total amount that needs to be
paid for dinner including tax = (13.75 + 0.69) dollars
                       = 14.44 dollars
Percentage of tips that they both want to leave = 15%
Then
Amount of tips that need to be given = (15/100) * 14.44
                              = 216.6/100 dollars
                              = 2.17 dollars
So
The total amount that they should leave = (14.44 + 2.17) dollars
                                 = 16.61 dollars
So they should leave a total of $16.61 in the restaurant.
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