A company's profit, $P$, in thousands of dollars, is linearly related to the number of units sold, $n$, in hundreds. The table below shows the profit for different numbers of units sold.

Units Sold (hundreds), $n$	Profit (thousands of dollars), $P$
5	15
10	25
15	35

If the company needs to make a profit of at least $40,000, what is the minimum number of units, to the nearest hundred, that must be sold?