The number of complaints received on 8 different days of two different models of mobile phones sold by a shop are as follows:
Model A: 22 18 25 20 16 17 12 22
Model B: 16 14 22 12 14 20 10 12 What measure of central tendency should be used to determine which model is better? Find the measure of this central tendency and state which model has better performance?

Answer

To determine which model of mobile phone has better performance based on the number of complaints received, we will calculate the mean (average) number of complaints for both models. The model with the lower mean number of complaints will be considered better.

### Step-by-Step Solution:

**Step 1: Calculate the Mean for Model A**
- List the complaints for Model A: 22, 18, 25, 20, 16, 17, 12, 22.
- Sum the complaints:
\[ 22 + 18 + 25 + 20 + 16 + 17 + 12 + 22 = 152 \]
- Count the number of observations: There are 8 days.
- Calculate the mean:
\[ \text{Mean of Model A} = \frac{\text{Sum of complaints}}{\text{Number of observations}} = \frac{152}{8} = 19 \]

**Step 2: Calculate the Mean for Model B**
- List the complaints for Model B: 16, 14, 22, 12, 14, 20, 10, 12.
- Sum the complaints:
\[ 16 + 14 + 22 + 12 + 14 + 20 + 10 + 12 = 130 \]
- Count the number of observations: There are 8 days.
- Calculate the mean:
\[ \text{Mean of Model B} = \frac{\text{Sum of complaints}}{\text{Number of observations}} = \frac{130}{8} = 15 \]

**Step 3: Compare the Means**
- Mean of Model A = 19
- Mean of Model B = 15

**Conclusion:**
Since Model B has a lower mean number of complaints (15) compared to Model A (19), Model B is considered to have better performance.