# Ex.3.1 Q7 Data Handling - NCERT Maths Class 7

## Question

The enrollment in a school during six consecutive years as follows: -

\(1555, 1670, 1750, 2013, 2540, 2820\)

Find the mean enrollment of the school for this period.

## Text Solution

**What is known?**

Number of enrollments

**What is unknown?**

Mean

**Reasoning: **

Mean enrollment

\[\begin{align} = \frac{{\left[ \begin{align} {\text{sum of numbers}}\\ {\text{of enrollments}} \end{align} \right]}}{{{\text{Total numbers of years}}}}\end{align}\]

**Steps:**

Total no. of years \(= 6\)

The enrollments in a school during six consecutive years

\[\left[ \begin{align}{\rm{ = 1555, 1670, 1750, }}\\{\rm{ 2013, 2540, 2820}}\end{align} \right]\]

Mean enrollment

\[\begin{align} &= \frac{{\left[ \begin{array}{l}{\text{sum of numbers }}\\{\text{of enrollment}}\end{array} \right]}}{{\left[ \begin{array}{l}{\text{Total numbers }}\\{\text{of enrollment}}\end{array} \right]}}\\ &= \frac{{\left[ \begin{array}{l}1555 + 1670 + 1750 + \\2013 + 2540 + 2820\end{array} \right]}}{6}\\& = \frac{{12348}}{6}\\ &= 2058\end{align}\]

Thus, the mean enrollment of the school is \(2058.\)