Since Max is paid 2.5% of his total sales T, then his total earnings are (2.5/100) times T plus his weekly salary:

The fraction 2.5/100 is equivalent to 1/40. Rewrite P using propper fractions:

His total pay for a week with a total sales of $4,650, is:

Therefore, Max is paid a total of $341.25 for a week in which his total sales are $4,650.