How many different numbers, greater than 50000 can be formed with the digits 0, 1, 1, 5, 9.

Numbers greater than 50000 can either have 5 or 9 in the first place and will consist of 5 digits.

Number of arrangements having 5 as the first digit $=\frac{4 !}{2 !}$

Number of arrangement having 9 as the first digit $=\frac{4 !}{2 !}$

$\therefore$ Required arrangements $=\frac{4 !}{2 !}+\frac{4 !}{2 !}=24$