Number puzzles with arithmetic operations

The number 999

Try to reach the number 999, by just taking the digit 9 six times.
You can use any arithmetic operation.

Solution (1): 9+99 + 9*99
Solution (2): (sqrt(9) + 9) * 9 + 99*9 = 999

The number 99

How can you decrease the number 99, without subtracting any number?

Solution:
The number can be reduced by just turning the digits (vertical flip): 66

The number 30

Try to reach the number 30, by just using the digit 5 four times.
You can combine any arithmetic operation.

The number 30 with 5 5 5 5:
Solution (1): 55 - (5 * 5) = 30
Solution (2): (5/5 + 5) * 5 = 30