The heights of 10 girls are measured (in cm) and the results are as follow
143, 148, 135, 150, 128, 139, 149, 146, 151, 132.
The mean height (in cm) of girls is

Options

A. `141.1 `
B. `142.1 `
C. `143.1 `
D. `140.2 `

Answer

To find the mean height of the 10 girls, we will follow these steps:

### Step 1: List the heights
The heights of the 10 girls are:
- 143 cm
- 148 cm
- 135 cm
- 150 cm
- 128 cm
- 139 cm
- 149 cm
- 146 cm
- 151 cm
- 132 cm

### Step 2: Calculate the sum of the heights
We will add all the heights together.
\[ \text{Sum} = 143 + 148 + 135 + 150 + 128 + 139 + 149 + 146 + 151 + 132 \]

### Step 3: Perform the addition
Calculating the sum step by step:
- \(143 + 148 = 291\)
- \(291 + 135 = 426\)
- \(426 + 150 = 576\)
- \(576 + 128 = 704\)
- \(704 + 139 = 843\)
- \(843 + 149 = 992\)
- \(992 + 146 = 1138\)
- \(1138 + 151 = 1289\)
- \(1289 + 132 = 1421\)

So, the total sum of the heights is \(1421\) cm.

### Step 4: Count the number of girls
The number of girls is given as \(10\).

### Step 5: Calculate the mean
To find the mean, we divide the total sum of the heights by the number of girls.
\[ \text{Mean} = \frac{\text{Sum}}{\text{Number of girls}} = \frac{1421}{10} = 142.1 \text{ cm} \]

### Final Answer
The mean height of the girls is \(142.1\) cm.

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