Mary worked 22 hours.
To solve first you would subtract the amount she made in tips from her total earnings (317-185)
= 132
Then you divide that answer by her hourly salary of $6 (132/6)
=22
2(8 4/5)+2(22/25)
2(44/5)+2(22/25)
2(220/25)+2(22/25)
(440/25)+(44/25)
484/25=P
The next number would be 8+13 = 21
