Question

What is the sum of a 28–term arithmetic sequence where the first term is 12 and the last term is 255?

Answer 1

http://openstudy.com/study#/updates/4fb2d452e4b055653428bd9e

Answer 2

wait..but i don't understand the formula.

Answer 3

for more on this topic:
Tutorial on AP,GP,HP.
http://openstudy.com/study#/updates/503bb2a0e4b007f9003103b0

Answer 4

couldn't you just work it out? i learn best from rereading.

Answer 5

sure ,
sum of n terms = n/2(1st term + last term)

Answer 6

= 28/2 (12+255)

Answer 7

=14*(267)
=3738
got it ?

Answer 8

wow i actually do..

Answer 9

thank you so much..

Answer 10

thats great :)

Answer 11

welcome ^_^

Answer 12

wait..

Answer 13

for the future..how do i tag people in a problem if noone will answer?

Answer 14

`@hartnn`

Answer 15

@rayford

Answer 16

tag me now

Answer 17

ok, i hate to be a burden but..for the next 2 days is it ok..if you be my tutor?

Answer 18

if i m online, i will be....else there are many to help u here :)

Answer 19

ok..but. do you think you will be online at 8 tomorrow?

Answer 20

my time zone maybe different, its 8 am here now....

Answer 21

oh man..it's 10:21 pm here

Answer 22

so means 10 hrs from now....
means at 6pm for me....most probably, i will be online, but cannot guarantee anything....

Answer 23

i absolutely understand.