Find the sum of the series.
12
σ 2k+14
k=1

What we'll do is plug integer values from 1 to 12 into the expression 2*k+14 like shown below:

if k = 1, then 2*k+14 = 2*1+14 = 16
if k = 2, then 2*k+14 = 2*2+14 = 18
if k = 3, then 2*k+14 = 2*3+14 = 20
if k = 4, then 2*k+14 = 2*4+14 = 22
if k = 5, then 2*k+14 = 2*5+14 = 24
if k = 6, then 2*k+14 = 2*6+14 = 26
if k = 7, then 2*k+14 = 2*7+14 = 28
if k = 8, then 2*k+14 = 2*8+14 = 30
if k = 9, then 2*k+14 = 2*9+14 = 32
if k = 10, then 2*k+14 = 2*10+14 = 34
if k = 11, then 2*k+14 = 2*11+14 = 36
if k = 12, then 2*k+14 = 2*12+14 = 38

Add up the results: 
16+18+20+22+24+26+28+30+32+34+36+38 = 324

The final answer is 324

Best answer that i found on yahoo ok   set :   x= length of 2nd piece in cm  x- 3= length of 1st piece in cm  x-4= length of 3rd piece in cm  then since you know they all came from the 20 cm ribbon you add them together and set them equal to 20x+ x-3 +x-4 = 20  3x - 7= 20  3x= 27  x= 9  the shortest piece is the third piece which is x- 4  x-4  9-4 = 5  the length of the smallest piece is 5 cm.  the other lengths are  9 cm  6 cm

A: 0.26 would be the answer