Answer:
a) What is the first term?
The first term is when she has the money during week #1, so the right answer is $138
b) What is the difference?
The difference is $55
c. What is the iterative rule for the amount Mrs. Speaks has after n weeks?
We use :
Un = a + (n - 1)d
which :
Un = iterative rule
a = first term
n = the n itself
d = difference on each weeks.
Un = 138 + (n - 1)55
Un = 138 + 55n - 55
Un = 83 + 55n
The answer is 83 + 55n
━━━━━━━━━━━━━━━━━
Hope it helps!
