Problem
31. Sue enjoys her coffee. She spends \( \$ 7.50 \) per day at the coffee shop each weekday. She brews her own on the weekends and spends \( \$ 40 \) a month on the ground coffee. How much is Sue spending annually on coffee? (a) \( \$ 2430 \) (b) \( \$ 3210 \). (c) \( \$ 870 \) (d) \( \$ 840 \)
Solution
Step 1 ：\(\text{Cost per weekday} = 7.50 \times 5 \text{ days} = \$ 37.50 \)
Step 2 ：\(\text{Cost per month} = 37.50 \times 4 \text{ weeks} + \$ 40 = \$ 190 \)
Step 3 ：\(\text{Annual cost} = 190 \times 12 \text{ months} = \$ 2280 \)
