Question

What is the sum of the arithmetic sequence 140, 134, 128..., if there are 33 terms?

1,364********
1,408
1,452
1,496

What is the sum of the arithmetic sequence 5, 11, 17 ..., if there are 24 terms?

1,684
1,776**********
2,020
2,182

What is the sum of a 17-term arithmetic sequence where the first term is 7 and the last term is -105?

-833
-893***
-913
-943

Answer 1

@Directrix

Answer 2

Please check my work .The *** indicate my answers.

Answer 3

1) Look at this. Somebody worked the problem on Open Study and got a different answer.
http://openstudy.com/study#/updates/4fad4adbe4b059b524f8e1ff

Answer 4

1) another answer to the same problem
http://openstudy.com/study#/updates/4fb6deade4b05565342ca790

Answer 5

Okay.

Answer 6

1) and yet another
http://openstudy.com/study#/updates/4f924e56e4b000310fafe7e0

Answer 7

What about the others?

Answer 8

I find it strange that the same question has appeared here and everyone seems to get a different answer. Quality control must not be up to par.

Answer 9

I believe the first 2 answers were the correct.

Answer 10

Are you satisfied that your #1 is correct?

Answer 11

Yes. I have the #1 now.

Answer 12

What about #2?

Answer 13

Im pretty positive about that, but what about #3?

Answer 14

1776 for #2?

Answer 15

Okay

Answer 16

Yes

Answer 17

I got them correct

Answer 18

I'm cranking out number 4 to check.

Answer 19

(7 - 105) * ( (17/2)) =

Answer 20

-833 ?

Answer 21

Yes

Answer 22

We have different answers:

-833
-893***
-913
-943

Answer 23

I continue to get - 833 for #4.

Answer 24

Confirmed that the answer to the last problem is -833.

Answer 25

Thanks. I did not get confirmation from @tinaballerina and was concerned.

Answer 26

You're welcome :)