(√99-√44)√11

First simplify the square roots:
√99 = √(911) = 3√11
√44 = √(411) = 2√11

Now, substitute back into the original expression:
(3√11 - 2√11)√11
= √11 (3-2)
= √11 1
= √11

Therefore, (√99-√44)√11 simplifies to √11.