Question

Which expression defines the arithmetic series 2.3 + 2.6 + 2.9 + for five terms

Answer 1

so a sub n=2.3+(n-1)0.3

That's in an arithmetic sequence

Answer 2

Option C is the answer.

Explanation:

Given arithmetic series is 2.3 + 2.6 +2.9 + ......... 5 terms

Since this series is an arithmetic series so explicit formula of series will be
`\sum_(n=1)^(n)[a+(n-1)d]` where a is the first term, d is the common difference and n is the number of term.

Therefore, we replace the values a = 2.3, and d = (2.6 - 2.3) = (0.3)

expression will be
`\sum_(n=1)^(n)[2.3+(n-1)(0.3)]`

`\sum_(n=1)^(n)[2.3+(0.3)n-0.3]`

`\sum_(n=1)^(n)[2+(0.3)n]`

Option C is the answer.