Question

A restaurant's average food preparation time was tracked from day to day as part of an efficiency improvement program.
Average food preparation time
Day Food preparation time (minutes)
Tuesday 23
Wednesday 21
Thursday 9
Friday 13
Saturday 7
According to the table, what was the rate of change between Wednesday and Saturday?
Round your answer to the nearest tenth.
minutes per day

Answer 1

To calculate the rate of change in food preparation time between Wednesday and Saturday, we first need to identify the food preparation times for those days from the table:

- Wednesday: 21 minutes
- Saturday: 7 minutes

The rate of change can be calculated using the formula:

\[
\text{Rate of change} = \frac{\text{Change in food preparation time}}{\text{Change in days}}
\]

1. Calculate the change in food preparation time:
\[
\text{Change in food preparation time} = \text{Time on Saturday} - \text{Time on Wednesday} = 7 - 21 = -14 \text{ minutes}
\]

2. Calculate the change in days:
- From Wednesday to Saturday is 3 days (Thursday, Friday, and Saturday).

3. Calculate the rate of change:
\[
\text{Rate of change} = \frac{-14 \text{ minutes}}{3 \text{ days}} \approx -4.67 \text{ minutes/day}
\]

Rounding to the nearest tenth, the rate of change is approximately:

\[
\text{-4.7 minutes per day}
\]

So, the answer is **-4.7 minutes per day**.