Question 164236
We first must find the implied interest rate of a $1200 investment earning $96 each year.  This can be found as {{{1200*r = 96}}} => {{{r = 96/1200 = .08}}}.  Therefore we are investing the $1200 at a 8% interest rate.
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Now we must use our newly found r to solve for a new investment balance.  We do this as follows: {{{p*.08 = 128}}} => {{{p = 128/.08 = 1600}}}.  Therefore, we would need to invest $1600 to earn $128 each year.