Question 1197706

I have invested $1200 in a bank acount with an interest rate 4.5% compounded monthly.  After how many years will my account pass $2100
<pre>Use the formula for the FUTURE VALUE of $1: {{{matrix(1,3, "A/FV", "=", P(1 + i/m)^mt)}}} 
                      For this problem: {{{matrix(1,3, P(1 + i/m)^mt, ">", "A/FV")}}}
                            {{{matrix(1,3, "1,200"(1 + .045/12)^(12t), ">","2,100")}}} ----- Substituting 1,200 for P, .045 for i, 12 for m, and 2,100 for A/FV
                                   {{{matrix(3,3, (1 + .045/12)^(12t), ">", "2,100"/"1,200", (12.045/12)^(12t), ">", 7/4, 1.00375^(12t), ">", 7/4)}}}

                                             {{{matrix(1,3, 12t, ">", log (1.00375, (7/4)))}}} ------ Converting to LOGARITHMIC form

                                               {{{matrix(2,3, t, ">", (log (1.00375, (7/4)))/12, t, ">", (log((7/4))/log((1.00375)))/12)}}}

                                     Time, or {{{highlight_green(matrix(1,11, t, ">", "12.45920918,", or, t, "=", highlight(12.5), or, highlight(12&1/2), (matrix(1,4, rounded, to, nearest, month)), highlight(years)))}}}</pre>