Question

The table shows the times, in minutes, spent shopping by two different groups. First, find the mean times each group spent shopping. Then determine the difference in the mean times.

group A 18 20 46 34 58 31 38
group B 15 21 32 42 29 57 28

(3 points)
The mean time Group A spent shopping is
minutes.

The mean time Group B spent shopping is
minutes.

The mean times Group A and Group B spent shopping differ by
minutes.

Answer 1

To find the mean time each group spent shopping, we need to calculate the average of the times for each group.

**Group A times:** 18, 20, 46, 34, 58, 31, 38

1. Calculate the sum of the times for Group A:
\[
18 + 20 + 46 + 34 + 58 + 31 + 38 = 245
\]
2. Count the number of members in Group A (which is 7).
3. Calculate the mean time for Group A:
\[
\text{Mean for Group A} = \frac{245}{7} = 35
\]

**Group B times:** 15, 21, 32, 42, 29, 57, 28

1. Calculate the sum of the times for Group B:
\[
15 + 21 + 32 + 42 + 29 + 57 + 28 = 224
\]
2. Count the number of members in Group B (which is also 7).
3. Calculate the mean time for Group B:
\[
\text{Mean for Group B} = \frac{224}{7} = 32
\]

**Calculate the difference in mean times:**
\[
\text{Difference} = |35 - 32| = 3
\]

So, to summarize:

- The mean time Group A spent shopping is **35 minutes**.
- The mean time Group B spent shopping is **32 minutes**.
- The mean times Group A and Group B spent shopping differ by **3 minutes**.