Texas BA II calculator

Hi Quick question , im having trouble with my calculator im trying to compute this question N = ? i = 5/12 PV = 35000 FV = 100,000 PMT = 0 when i try to calculate i get an error 5, what am i doing wrong, sorry it must be so obvious any help would be appreaciated cheers

either one of PV or FV must be a -ve value. Remember - one of them is an inflow, the other an outflow. CP

PV or FV needs to be set to a negative (-) correct way is to set PV to negative as you are spending/investing it ie an outflow