Question

One week, Heather opens a bank account with $125. Each week, starting the second week, she deposits $25 into her account. What is the explicit rule for amount of money Heather has in her account after n weeks?

Answer 1

I think your answer is
a(n) = 125 + 25n

Answer 2

Answer:

The explicit rule for amount of money Heather has in her account after n weeks is $f(n)=100+25n$.

Step-by-step explanation:

It is given that Heather opens a bank account with $125. Each week, starting the second week, she deposits $25 into her account.

It means the initial amount is 125 and the common difference is 25. The sequence is

125, 150, 175,...

The explicit rule is

$f(n)=a+(n-1)d$

Where, a is first term and d is common difference.

The explicit rule for amount of money Heather has in her account after n weeks is

$f(n)=125+(n-1)25$

$f(n)=125+25n-25$

$f(n)=100+25n$

Therefore the explicit rule for amount of money Heather has in her account after n weeks is $f(n)=100+25n$.