Relevant info with question following:

A homeowner can obtain a $350,000, 30-year fixed-rate mortgage at a rate of 6.0 percent with zero points or at a rate of 5.5 percent with 2.5 points.How long must the owner stay in the house to make it worthwhile to pay the points if the payment savings are invested monthly?

Monthly PMT No Points:

N=360, I/Y=6/12, PV=350,000, PMT=? FV=0 PMT= 2,098.43

Monthly Payment Loan with Points:

N=360, I/Y=5.5/12, PV=350,000 PMT=?, FV=0, PMT = 1987.26

Savings: 2098.43-1987.26 = $111.17

Points = 350,000 x .025 = $8,750.00

************QUESTION*******

With the above work completed already, how long must the owner stay in the house to make it worthwhile to pay the points if the payment savings are invested monthly?

Please explain using N, I/Y, PV, PMT, FV is possible. Last tutor who answered used excel and I would appreciate an explanation with the calculator inputs/concept. Thank you!