Question

Khalil, a doctor's office receptionist, tracked the average waiting time at the office each month.
Average waiting time at a doctor's office
Month Waiting time (minutes)
May 39
June 49
July 50
August 49
September 40
According to the table, what was the rate of change between June and September?
minutes per month

Answer 1

To find the rate of change in average waiting time from June to September, we can use the formula for rate of change:

\[
\text{Rate of Change} = \frac{\text{Change in Waiting Time}}{\text{Change in Time}}
\]

1. Identify the waiting times for June and September:
- June waiting time: 49 minutes
- September waiting time: 40 minutes

2. Calculate the change in waiting time:
\[
\text{Change in Waiting Time} = \text{Waiting time in September} - \text{Waiting time in June}
\]
\[
\text{Change in Waiting Time} = 40 - 49 = -9 \text{ minutes}
\]

3. Calculate the change in time:
- From June to September is a span of 3 months (July, August, September).

\[
\text{Change in Time} = 3 \text{ months}
\]

4. Now, calculate the rate of change:
\[
\text{Rate of Change} = \frac{-9 \text{ minutes}}{3 \text{ months}} = -3 \text{ minutes per month}
\]

Thus, the rate of change between June and September is **-3 minutes per month**.