Chapter 12.1, Problem 46E

To determine

Calculate the sum of the equation.

Answer to Problem 46E

The sum of the equation is $90$ .

Explanation of Solution

Given:

It is given in the equation that the equation is ${\displaystyle \sum _{i=4}^{12}10}$ .

Concept Used:

In this use the concept of, putting the number in the equation and expand it.

Calculation:

Here, the equation is ${\displaystyle \sum _{i=4}^{12}10}$ .

Here, the difference between the two numbers $4and12$ is $9$ by seeing the counting. So the number $10$ is written $9$ times .

  $\begin{array}{l}{\displaystyle \sum _{i=4}^{12}10}=10+10+10+10+10+10+10+10+10\\ {\displaystyle \sum _{i=4}^{12}10}=90\end{array}$

Conclusion:

The sum is $90$ .