The biggest issue with word problems is trying to decide which operation to do.
Let's write a similar story with easier numbers.
Mary is making up sweet packets. She has 36 sweets left and want to put 4 sweets in each packet. How many packets can she make?
She is sharing out the sweets and using 4 at a time in each packet.
It is a division:
In the same way, Diana has
It is a division.
Multiply straight across:
She can paint