I just need help with this.

Question

Write the series in sigma notation.

1/4 + 1/2+ 3/4 + 1 + 5/4 + 3/2

5
A.) 1/4 sigma N
n=1

6
B.) 1/4 sigma n
n=1

5
C.)sigma n/n+3
n=1

6
D.)sigma n/n+3
n=1

Answer 1

rewrite it as:
1/4 + 1/2+ 3/4 + 1 + 5/4 + 3/2
= 1/4 + 2/4 + 3/4 + 4/4 + 5/4+ 6/4
= (1/4)(1+2+3+4+5+6)
so I see 6 terms of natural numbers

= (1/4)∑ n , with n=1 below the ∑ sign, and 6 above it

looks like choice B is the one.