2.17 Related Rates: Quiz
Problem 5
A savings account is set up so that a regular deposit of $150 is made every month. The account earns interest, and the interest varies according to the amount in the account: An account with balance B less than $100 earns no interest; otherwise, the interest rate is 2.7% plus .05% for each $1000 in the account, up to $10,000.
Find the rate of change of interest I with respect to time t.