Question

Calculate the mean of the first 20 natural numbers.

Answer 1

Hint: Find the first 20 natural numbers starting from 1. Then find the mean which is the average of the numbers. i.e. the sum of 20 natural numbers by total number.

Complete step-by-step answer:

Natural numbers are those which are used for counting and ordering. The natural number starts from 1, corresponding to the positive integers.

1, 2, 3, …….

We are asked to find the mean of the first 20 natural numbers.

We know the first 20 natural numbers are,

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20

We know the formula that, Mean = Sum of the numbers / Total numbers.

$$\therefore$$ Mean of first 20 natural numbers = Sum of first 20 natural numbers / 20.

$$\begin{array}{rl}& ={\displaystyle \frac{1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20}{20}}\\ & ={\displaystyle \frac{210}{20}}\\ & =10.5\end{array}$$

Hence, we got the mean of the first 20 natural numbers = 10.5.

Note: Remember that zero is not a natural number: zero is considered as a whole number, which makes zero an integer, but it doesn’t make it a natural number. We cannot start counting without saying the most important numbers. We don’t count something if there is zero of it. So, zero is not a natural number.