The body weight of six boys is recorded as 42kg, 72kg, 85kg, 64kg, 54kg and 73kg. What is the average body weight of all six boys?

Options

A. 64kg
B. 67kg
C. 62kg
D. 65kg

Answer

To find the average body weight of the six boys, we will follow these steps:

### Step 1: List the weights of the boys.
The body weights of the six boys are:
- 42 kg
- 72 kg
- 85 kg
- 64 kg
- 54 kg
- 73 kg

### Step 2: Calculate the sum of the weights.
We need to add all the weights together:
\[ 42 + 72 + 85 + 64 + 54 + 73 \]
Calculating this step-by-step:
- First, add 42 and 72:
\[ 42 + 72 = 114 \]
- Next, add 85:
\[ 114 + 85 = 199 \]
- Then, add 64:
\[ 199 + 64 = 263 \]
- Now, add 54:
\[ 263 + 54 = 317 \]
- Finally, add 73:
\[ 317 + 73 = 390 \]

So, the total sum of the weights is **390 kg**.

### Step 3: Count the number of boys.
The number of boys is given as 6.

### Step 4: Calculate the average weight.
Now, we use the formula for average:
\[ \text{Average} = \frac{\text{Sum of weights}}{\text{Number of boys}} = \frac{390}{6} \]
Calculating this:
\[ \frac{390}{6} = 65 \]

### Conclusion:
The average body weight of all six boys is **65 kg**.

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