Question

If the heights of $5$ persons are ${\text{140 cm}}$,${\text{150 cm}}$,${\text{152 cm}}$,${\text{158 cm}}$ and ${\text{161 cm}}$ respectively, find the mean height.

Answer 1

Hint: Here we have to find the mean height. Also we have a given data and using the formula for mean. After doing some simplification we get the required answer.

Formula used: ${\text{Mean = }}\dfrac{{{\text{sum of terms}}}}{{{\text{number of terms}}}}$

Complete step by step solution:
From the question it is given that the total number of people in the distribution is $5$, therefore the number of terms $ = 5$.
Now to find the mean, the formula is:
${\text{Mean = }}\dfrac{{{\text{sum of terms}}}}{{{\text{number of terms}}}}$
On substituting the values of all the terms, we get:
${\text{Mean = }}\dfrac{{140 + 150 + 152 + 158 + 161}}{5}$
On adding all the terms in the numerator, we get:
${\text{Mean = }}\dfrac{{761}}{5}$
Let us divide the term and we get:
${\text{Mean = 152}}{\text{.2}}$, which is the required answer.

Therefore, the mean height of all the persons in $152.2$

Note: Mean is called average in layman terms and it is always the total of a value of a property in a distribution divided by the total number of terms in that distribution. There also exists median and mode of a distribution.
Mean is not used when there are extreme values in the distribution. In these cases, the median is used; it tells which term is the middle term when all the terms are arranged in ascending order.