Doesn't seem too hard...
First work out what the numbers mean.
Which is hours worked, which is the rate and which is the age?
Base pay: Does Donald work more or less than 40 hours?
If more, what does he get paid for the 40 hours, and what does he get
paid for the extra time?
Tax: is Donald older or younger than 55?
If he's older, what would the rate be?
How would you calculate the tax from the amount paid and the rate?