Question

Julie opens an account with $350 anddeposits $75 at the end of each month. Heraccount balance at the end of each monthcan be represented by the function f(n) =75n + 350.a. How many months will it take for Julieto have $1175?b. What is a recursive rule that describesthis situation?

Answer 1

Julie opens an account with $350 and deposits $75 at the end of each month.

let the number of months = n

the account balance can be represented by f(n) = 75 n + 350

A) The number of months to have $1175:

so, 1175 = 75 n + 350

solve for n

75 n = 1175 - 350 =

75 n = 825

divide both sides by 75

so, n = 825/75 = 11 months

so, 11 months to have $1175

B) What is a recursive rule that describes this situation?

it is like arithmetic sequence

the first term = 350 + 75 = 425

the common difference = 75

so, the rule will be = 425 + 75 (n - 1)