Answer: Choice b
2.50C + 3.25B ≤ 35
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Work Shown:
C = number of cupcake boxes
B = number of brownie boxes
2.50C = cost of the cupcakes only
3.25B = cost of the brownies only
2.50C + 3.25B = total cost
total cost ≤ 35
2.50C + 3.25B ≤ 35