How much does Mike spend weekly on coffee if he buys coffee every weekday and goes out on Saturday?

To determine how much Mike spends weekly on coffee, we first need to understand his coffee-buying habits. He purchases coffee every weekday, which consists of five days, and he also buys coffee on Saturday, leading to a total of six days of coffee purchases in a week.

If we consider an average price for each cup of coffee that Mike buys during these six days, we can multiply this price by the number of days he purchases coffee to arrive at his total weekly expenditure.

Choosing the option that reflects his total weekly spending correctly requires ensuring that the sum aligns with reasonable assumptions about coffee prices and his habit. If the summation aligns with option D, it suggests that the calculated total made sense based on the given frequency of coffee purchases throughout the week.

Thus, by confirming the weekly coffee expenditure through this reasoning process, we arrive at the conclusion that Mike spends $21.78 weekly on coffee, which corresponds to option D. This total accurately portrays both his weekday and Saturday coffee purchases.