To find the mean shopping times for Group A and Group B, we need to calculate the average time spent by each group.
Step 1: Calculate the mean for Group A.
Group A times: 18, 20, 46, 34, 58, 31, 41
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Calculate the sum of Group A's times: \( 18 + 20 + 46 + 34 + 58 + 31 + 41 = 248 \)
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Count the number of entries in Group A: \( 7 \)
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Calculate the mean: \[ \text{Mean}_A = \frac{\text{Sum of Group A}}{\text{Number of entries}} = \frac{248}{7} \approx 35.4 \]
Step 2: Calculate the mean for Group B.
Group B times: 15, 21, 32, 42, 29, 57, 39
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Calculate the sum of Group B's times: \( 15 + 21 + 32 + 42 + 29 + 57 + 39 = 235 \)
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Count the number of entries in Group B: \( 7 \)
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Calculate the mean: \[ \text{Mean}_B = \frac{\text{Sum of Group B}}{\text{Number of entries}} = \frac{235}{7} \approx 33.6 \]
Step 3: Determine the difference in mean times.
- Calculate the difference: \[ \text{Difference} = \text{Mean}_A - \text{Mean}_B = 35.4 - 33.6 = 1.8 \]
Final Answers:
- The mean time Group A spent shopping is approximately 35.4 minutes.
- The mean time Group B spent shopping is approximately 33.6 minutes.
- The mean times Group A and Group B spent shopping differ by 1.8 minutes.