My teacher marked it wrong, but l don't know why

[BK1113]

Melinda is planning to attend a private university after she graduates from high school in three years. She is devising a plan to save money each month to help with the expenses of attending the university. The cost of attending the private university for 1 year is $22,500. Her family has promised to contribute $13,500 each year she is in school. Which plan shows the minimum amount of money Melinda must contribute to her savings to have enough money to pay for her first year of tuition?
A. Save $250 per month for the next 3 years
B. Save $375 per month for the next 3 years
C. Save $625 per month for the next 3 years
D. Save $750 per month for the next 3 years

I chose D. because $22,500 - $13,500 = $9,000. $9000÷12 months is $750.

My teacher marked this one wrong, but l keep getting the same answer.

 

[Deleted member 4993]

Melinda is planning to attend a private university after she graduates from high school in three years. She is devising a plan to save money each month to help with the expenses of attending the university. The cost of attending the private university for 1 year is $22,500. Her family has promised to contribute $13,500 each year she is in school. Which plan shows the minimum amount of money Melinda must contribute to her savings to have enough money to pay for her first year of tuition?
A. Save $250 per month for the next 3 years
B. Save $375 per month for the next 3 years
C. Save $625 per month for the next 3 years
D. Save $750 per month for the next 3 years

I chose D. because $22,500 - $13,500 = $9,000. $9000÷12 months is $750.

My teacher marked this one wrong, but l keep getting the same answer.

Melinda has 36 months (3 * 12) to save that amount.

So the expected amount is 250/month.

However, this does not take into account the amount of interest she might accrue.

 

[BK1113]

Thank you!