The problem number 1 is the question. See attached photo.

Answer:
[tex]\sum\limits^5_{n =1} n = 15[/tex]
Step-by-step explanation:
Given
[tex]\sum\limits^5_{n =1} n[/tex]
Required
Compute
This implies that we add n whose value ranges from 1 to 5.
So:
[tex]Sum = 1 + 2 + 3 + 4 + 5[/tex]
[tex]Sum =15[/tex]
Hence:
[tex]\sum\limits^5_{n =1} n = 15[/tex]