Answer:
Donuts(b) = 12*b
Step-by-step explanation:
Notice that the question is:
What's an expression to model the number of donuts in b boxes?
We know that we are talking of boxes of a dozen donuts.
We know that in one dozen, we have 12 donuts.
Then if we have b boxes, and in each box we have 12 donuts, we will have a total of b times 12 donuts, the expression is:
Donuts(b) = 12*b
There is a lot of information here that we did not use (like the cost of cardboard and donuts), and that may be there just to distract us, the important thing to do here is:
See what is the thing we want to find (in this case, the number of donuts in b boxes)
Find the relevant information to solve this. (ignore the irrelevant information)
Solve the question.