Help me plant my bananas please!

Hey there, so I got an issue.
A friend of a friend of mine is trying to plant banana bushes. Each day she's going to plant one additional bush in her backyard and expects every bush there to produce 4.5 bananas a day.
Easy, that. But she has competition in the banana business. Her competitor is out there hunting 200 wild bananas a day. No more, no less.
Now we're trying to find out after how many days of planting her bushes her herd of home grown bananas will start outcompeting the hunts of her competition.

More specifically how would we formulate this as a function?
Our hunting competitor is a simple linear function we're pretty sure, but how could we express her planting endeavours properly?