To determine how much the average amount of flour in the bag changes each day when using a 15-pound bag of flour over four days, we can perform the following calculation:
- Total amount of flour: 15 pounds
- Number of days: 4 days
To find the average amount of flour used per day, you would divide the total amount of flour by the number of days:
\[ \text{Average amount of flour used per day} = \frac{\text{Total amount of flour}}{\text{Number of days}} = \frac{15 \text{ pounds}}{4 \text{ days}} = 3.75 \text{ pounds per day} \]
Therefore, the average amount of flour in the bag changes by 3.75 pounds per day as flour is used.
Since the bag starts with 15 pounds, the amount of flour in the bag at the end of each day would be:
- End of Day 1: 15 - 3.75 = 11.25 pounds
- End of Day 2: 11.25 - 3.75 = 7.5 pounds
- End of Day 3: 7.5 - 3.75 = 3.75 pounds
- End of Day 4: 3.75 - 3.75 = 0 pounds
Each day, on average, the amount of flour in the bag decreases by 3.75 pounds.