Quantcast

A community for students. Sign up today!

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

grant.orton

  • one year ago

how do you find the sum of a list of numbers.... ex.... 8,16,....312,320

  • This Question is Open
  1. grant.orton
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I know you have to find the average and multiply with the count or somthing like that

  2. apple_pi
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    This is an ARITHMETIC series: It goes up by a constant number. To sum this, first figure out how many terms there are in the series. Let the terms be denoted as such: T1 = 8 T2 = 16 ... Tn = 8n. So if Tn = 320 = 8n then n = 40. Therefore you have 40 terms. Now to sum the series you multiply the number of terms by the average of the first and last terms. Then divide by 2. \[\frac{40(8+320)}2=6560\]

  3. apple_pi
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I can explain why this works if you like

  4. Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Ask a Question
Find more explanations on OpenStudy

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...

23

  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.