### Home > PC > Chapter 2 > Lesson 2.3.2 > Problem2-85

2-85.

Express $2+2.5+3+3.5+\dots+9.5$ using sigma notation. (Do not find the sum).

The terms in this series are linear. The first term is $2$, the second term is $2.5$, etc. Think about how you could write the equation of a line passing through the points $(1,2)$ and $(2,2.5)$.