Philip makes $11.40 an hour plus time and a half for over time. Calculate his gross pay if he works 45 hours in a week.

p = 11.4*40 + 3/2 * 11.4 * (45-40) = 541.50

To calculate Philip's gross pay, we need to consider his regular pay rate and the overtime pay rate.

1. Regular Pay: Philip makes $11.40 an hour. Since he works 45 hours, his regular pay will be calculated for the first 40 hours.
Regular Pay = Regular Hours Worked x Hourly Rate
Regular Pay = 40 hours x $11.40/hour = $456

2. Overtime Pay: Philip receives time and a half his hourly rate for any hours worked beyond 40 hours. Since he has worked 45 hours in total, we need to calculate the overtime pay for the extra 5 hours.
Overtime Pay = Overtime Hours x (Hourly Rate x 1.5)
Overtime Pay = 5 hours x ($11.40/hour x 1.5) = $85.50

3. Gross Pay: To calculate the gross pay, we sum up the regular pay and the overtime pay.
Gross Pay = Regular Pay + Overtime Pay
Gross Pay = $456 + $85.50 = $541.50

Therefore, Philip's gross pay for working 45 hours in a week would be $541.50.