Respuesta :

akephd
21+16+28+19+x/5=18 (you are finding the missing number of 5 numbers to have a mean of 18)
84+x/5=18
Cross multiply and solve for x
84+x=90
So x, your final number of problems given a Friday, is 6.

Check: 84+6/5=90/5=18
salush
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