In: Finance
The fund accumulated in IRA can be calculated using excel's FV function.
FV(Rate,NPER,PMT,PV,TYPE)
Rate = 13%
NPER = 35 (for case (a)) & 25 (for case (b))
PMT = $2,400
PV = 0 (as there is no value in the fund as of now)
TYPE = 0 (which indicates end of the period)
See the image below