Here are some suggestions but you'll need to work through the details:

Define the random variable .

1. Note that .

2. You need to find the minimum integer value of n that solves where is the pdf of .

3. Standard result (from order statistics): Let denote continuous random variables with cdf F(x) and pdf f(x).

Define the random variable .

Then the pdf of is given by .

4. In your problem, for and zero otherwise.

Therefore the pdf of is given by .

5. I get n = 29 (whew! That's a relief)