If cookies sell $1 and oranges for 75 cents, how many of each were sold for a total of $8.25

There are multiple solutions:

3 oranges, 6 cookies

8 oranges, 3 cookies

11 oranges, 0 cookies

Step-by-step explanation:

There are multiple solutions.

For the decimal 0.25, we know that either 3, 7 or 11 oranges were sold.

If 11 oranges were sold, they cost 0.75*11=8.25 dollars, and thus no cookies were sold.

If 8 oranges were sold, they cost 0.75*8=5.25 dollars, and thus 8.25-5.25=3 cookies were sold.

If 3 oranges were sold, they cost 0.75*3=2.25 dollars, and thus 8.25-2.25=6 cookies were sold.