On 2 November 2006, Henry saved $1200 in an account that pays 8.6% per annum simple interest. Three years later, he added another $500 into the account. Find the amount in his account on 2 November 2012

Answer 1

1200(1+.086*6) + 500(1+.086*3)
or
1200(1+.086*3) + 1700(1+.086*3) = 2900(1+.086*3)