Question

Jobie starts with $325 in her piggy bank. Each month she adds $10.

Which recursive function rule models the total amount in Jobie’s piggy bank at the end of each month?

an=10⋅an−1 ​ and a1=325

an=10+an−1 ​ and a1=325

an=325⋅an−1 and a1=10

an=325+an−1 and a1=10

Answer 1

I think it is the fourth one

Answer 2

A recursive formula represent the nth terms of a sequence in terms of it's previous (n-1)th term and it include first term.

Let's assume,

`a_(1)` = First term,

`a_(n)` = nth term,

`a_(n-1)`= Previous term of nth term or (n-1) the term.

According to the problem,

Jobie starts with $325 in her piggy bank. Each month she adds $10.

Which means first term:
`a_(1) = 325`

Since he is adding $10 each month. So, this month if he will have
`a_(n-1)` then in the next month he will have
`10+a_(n-1)`.

So, the recursive formula will be ,

`a_(n) =10+a_(n-1) , a_(1) =325`