If a book costs $15 and David bought 50 copybooks, what is the total cost if he purchased an additional 5 books?

To determine the total cost of David's purchase, you first need to calculate the cost of the initial purchase of the 50 copybooks, followed by the cost of the additional 5 books.

1. The cost of one book is $15. Therefore, the total cost for 50 copybooks is calculated as follows:

( 50 \text{ copybooks} \times 15 \text{ dollars per copybook} = 750 \text{ dollars}. )

2. Next, calculate the cost for the additional 5 books:

( 5 \text{ books} \times 15 \text{ dollars per book} = 75 \text{ dollars}. )

3. Finally, add the total cost of the copybooks and the additional books together:

( 750 \text{ dollars} + 75 \text{ dollars} = 825 \text{ dollars}. )

Upon reviewing the calculations, it appears there was an error in interpreting the totals provided in the answer options, as the addition is not matching the expected range. The correct total amount for the multiple purchases, when correctly calculated iteratively, should indeed give a final aggregated cost of $825, which does not adhere to the options