The body weight of seven boys is recorded as 70 kg, 64 kg, 55 kg, 81 kg, 45 kg, 76 kg and 92 kg. What is the average body weight of all seven boys?

Correct option is A

Given:

The body weights of seven boys are:

$$70 \, \text{kg}, \, 64 \, \text{kg}, \, 55 \, \text{kg}, \, 81 \, \text{kg}, \, 45 \, \text{kg}, \, 76 \, \text{kg}, \, 92 \, \text{kg}$$​

The formula to calculate the average is:

$$\text{Average} = \frac{\text{Sum of all observations}}{\text{Number of observations}}$$​

1. Calculate the sum of the weights:

$$\text{Sum} = 70 + 64 + 55 + 81 + 45 + 76 + 92$$​

$$\text{Sum} = 483 \, \text{kg}$$​

2. Divide the sum by the number of boys (7):

$$\text{Average} = \frac{483}{7}$$​

Performing the division:

$$\text{Average} = 69 \, \text{kg}$$​

Final Answer:

The average body weight of all seven boys is $$69 \, \text{kg}$$​.