How to calculate the Net Pay for my employees with their overtimes?

I found this qestion in the qestion booklet of the Pacific Senior School Certificate in the year 2004. Here is the real qestion;

(Normal working hours are 35 hours a week. All overtime hours in excess of 35 hours a week shall be paid at one and a half times the normal rate. G. Watisoni ( an employee ) works for 50 hours in that week and his hourly rate is $12.00. He also has some dedutions such as $76. for the income tax, health insurance $10.50 and union fees $4.) Requirement is to calculate the his gross pay and his net pay as well. Also this qestion is taken from the topic as PAYROLL ACCONTS. I have spent many times to find the correct answer but could not find it.So please give me your hand to find it and I will be very thankful for your support.How to calculate the Net Pay for my employees with their overtimes?
Gross pay: $12 x 35 hours plus $18 x 15 hours

Deductions -

fixed: $10.50 + $4

variable: $76 for the 35 hours is about 18.1%, so an additional $48.85 or so for tax on the overtime pay.



Subtract deductions from gross pay and you get the net pay.How to calculate the Net Pay for my employees with their overtimes?
(35 x $12) + (15 x $18) = gross pay.



Net pay = gross pay minus deductions

Deductions being $76 + $10.50 + $4
Gross pay in this case would be (35 hrs x $12/hr) + (15 hrs x $12/hr x 1.5) = $690.



Net pay is gross pay less all deductions, in this case $690.00 - $76 - $10.50 - $4.00 = $599.50
50 - 35 = 15

15 x 18.00 plus 35 x 12 = 690.00 gross

(deductions)

76 + 10.50 + 4. = 90.50



690.00 - 90.50 = 599.50 net