Aril and Dita are wealthy Norwegian business owners who make monthly donations to international disaster relief.
Aril donated 150 Norwegian kroners (kr) the first month, and the cumulative number of Norwegian
kroners she has donated increases by a factor of 2.5 each month.
Dita donated 300 kr the first month, and the cumulative number of Norwegian kroners she has
donated increases by 400 kr each month.
They started making donations at the same time, and they both make their monthly donations at the
beginning of each month.
What is the first month in which Aril's cumulative donation exceeds Dita's cumulative donation?