Answer:
Increase in Peter's weekly gross salary is $32.30
Explanation:
Peter works 38 hours per week and earns $7.25 per hour.
Then weekly gross pay = 38×7.25 = $275.50
His employer gives him a rise so that his gross pay increases to $307.80
Now we can calculate the weekly gross increase in the pay by subtracting the pay after increase from the pay before the increase = 307.80 - 275.50
= $32.30
Therefore, increase in Peter's weekly gross salary is $32.30