What is the sum of the arithmetic sequence 8, 15, 22 …, if there are 26 terms?

Question

karatechopper · Answer

ok well first find the pattern

anonymous · Answer

2483

karatechopper · Answer

:/ ok fine go with answer

anonymous · Answer

Sorry, I'm new here...

karatechopper · Answer

its ok:) im just kiddin:) would u like to take a tour of openstudy?

myininaya · Answer

8                                         1st                                   
8+7                                     2nd    -> 1 seven
8+7+7                                 3rd    -> 2 sevens
8+7+7+7                             4th    ->  3 sevens
8+7+7+7+7                        5th     -> 4 sevens

....


so we have the answer can be found by looking at:
We have 26 terms ( so we will have 25 sevens)
8+25(7)

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Also ya we shouldn't just give the answer. We need to explain it okay @mathematicalnoob .
thanks.

karatechopper · Answer

how about we take this in the chat:) lets let them work the math problem out

anonymous · Answer

No at the moment, I'm actually waiting for an answer to my post so I can finish some homework but later :)

karatechopper · Answer

ok!:D

myininaya · Answer

wait oops not finish one second

lgbasallote · Answer

nice going there @karatechopper *wink* *wink* hehe

myininaya · Answer

8, 8+7,8+2(7),8+3(7),....8+25(7)
that term i gave you was the 26th term
so we are still on our way to the correct answer

karatechopper · Answer

huh? @lgbasallote

myininaya · Answer

$$\sum_{i=0}^{25}(8+i \cdot 7) $$

myininaya · Answer

You should be able to get it from there using some formulas :)