A baker sells pastries for $5 and works 7 days a week. On Monday he sold 2. Every day the number of sales increases by 1 compared to the previous day. On average, how many pastries does he sell on each day of the week? Let's think first. Chain of thought:
You know from the statement that on Monday he sells 2 pastries, so on Tuesday he sells 3, Wednesday 4, Thursday 5, Friday 6, Saturday 7 and Sunday 8 pastries. So the average value is (2 + 3 + 4 + 5 + 6 + 7 + 8) pastries / 7 days. The baker sells, on average, 35 / 7 = 5 pastries / day for 1 week.
Therefore, the answer is 5.