Diep is saving money so he can buy a used car in 12 months. the total cost of the car he wants is $1,450. diep determines that he needs to save $120 each month to be able to afford the car, as shown below. mc024-1.jpg what error did diep make? there is a subtraction error. diep will need to save less than $120 each month. there is a subtraction error. diep will need to save exactly $121 each month. there is a multiplication error. diep needs to save exactly $120.83 each month. there is a multiplication error. diep needs to save an average of mc024-2.jpg each month. some months he needs to save $120.83 and other months he needs to save $120.84.