Question

7.75?

Answer 1

first step: write out the explicit formula for the series

Answer 2

yes I did and got 7.75

Answer 3

an = (0.25) + (n-1)(0.25)

then use the sum formula

Answer 4

for n = 31

Answer 5

so 31=

Answer 6

a1 = 0.25
a31 = 7.75

^ plug these into the sum formula

Answer 7

8

Answer 8

^ plug a1, an, and n into this formula

Answer 9

so 31(0.25+7.75)

Answer 10

good but don't forget the /2 at the end

Answer 11

31(0.25+7.75)/2 = ?

Answer 12

124

Answer 13

good, so $124 is it

Answer 14

since they're asking for the total amount of money saved over 31 days you would use the sum

Answer 15

a31 = $7.75 only tells you how much money they deposited on day 31

Answer 16

oh okay