Answer:
165
Step-by-step explanation:
The symbol [tex]\sum[/tex] is used to denote a sum of multiple terms.
The number below [tex]\sum[/tex] is the first term.
The number above [tex]\sum[/tex] is the last term.
Each term can be determined by using the given equation.
[tex]\begin{aligned}\displaystyle \sum_{n=3}^{8}5n & =5(3)+5(4)+5(5)+5(6)+5(7)+5(8)\\ & = 5(3+4+5+6+7+8)\\ & =5(33)\\ & = 165\end{aligned}[/tex]
