Final answer:
Denise originally earns $7.50 per hour and after a 10% pay increase, her hourly rate becomes $8.25. Working 30 hours a week, her new weekly earnings are $247.50, previously being $225.00. Therefore, Denise will earn an additional $22.50 per week after the increase.
Step-by-step explanation:
To calculate the additional amount Denise will earn each week after a 10% pay increase, we first need to determine her new hourly wage. Since she originally earns $7.50 per hour, a 10% increase would be 0.10 x $7.50 = $0.75. Therefore, her new hourly wage will be $7.50 + $0.75 = $8.25.
Next, we multiply her new hourly wage by the number of hours she works each week. Denise works 30 hours per week, so her total earnings per week at the increased rate would be 30 hours x $8.25 = $247.50. Prior to the increase, she earned 30 hours x $7.50 = $225.00 per week.
Lastly, we subtract the original weekly earnings from the new weekly earnings to determine the increase in her weekly income. $247.50 - $225.00 = $22.50. Thus, Denise will earn an additional $22.50 each week after the pay increase.