Question

ennifer has been saving for college for 57 months. The first month, she saved $11. She was able to save more money each month than the month before. She ended up saving $19,779.00. How much more did she save each month?

Answer 1

@phi

Answer 2

@peachpi

Answer 3

What do you think? :)

Answer 4

I'm thinking the final amount is the sum of an arithmetic series and they want you to find the common difference of the sequence

Answer 5

I agree!

Answer 6

But I just dont know how to do it hahah

Answer 7

Use this one to find \(a_{57}\), the amount saved in the 57th month.
\[S_{57}=\frac{ n }{ 2 }(a_1+a_{57})\]
n = 57 and \(a_1=11\)

Answer 8

ok so s57=28.5(11+a57)

Answer 9

Right and S_57 = 19779

Answer 10

now what do we do?

Answer 11

solve for \(a_{57}\)

Answer 12

What would I divide by?

Answer 13

28.5

Answer 14

694

Answer 15

subtract 11

Answer 16

683

Answer 17

that's the 57th term. This is the formula to find d\[a_n=a_1+d(n-1)\]
\[683=11+d(57-1)\]

Answer 18

683=57d-d+11

Answer 19

11.78=answer

Answer 20

But the answer choices are
11.00
11.50
12.00
12.50

Answer 21

683=11 + 56d

Answer 22

672 = 56d

Answer 23

12:)

Answer 24

yes

Answer 25

Thanks :) If I open anothe question, will u answer it?