Question

Write the sum using summation notation, assuming the suggested pattern continues.

-4 + 5 + 14 + 23 + ... + 131

Answer 1

First, what is summation notation?

Answer 2

Great, so what do you notice about the series of numbers. How do they progress?

Answer 3

by 9

Answer 4

would that be the answer?

Answer 5

or would it be (-4+9n)?

Answer 6

Well, if you go from n=0 to n=132 then you have \[\sum_{0}^{130}-4+9n\]

Answer 7

You have to have the first term as -4, so you got it on the second try. :)

Answer 8

I made an error.

Answer 9

n should go to 15 not 130, -4+9*15=131

Answer 10

I apologize

Answer 11

thank you so much. you helped alot