Harolds RRSP is already worth $56,000. Rounding n to the next higher integer, how long will it

Question:

Harold’s RRSP is already worth $56,000. Rounding n to the next higher integer, how long will it take the RRSP to reach $250,000 if additional contributions of $2000 are made at the end of every six months? Assume the RRSP earns 9.75% compounded monthly.