1. ( 5 + 5 + 5 +5 ) x 5 = 100.

2. (5 x 5 x 5) -(5 x 5) = 100.

3. 5! -( 5 +5 + 5 + 5) = 100.

4. ( 5 x 5 ) x ( 5 - ( 5 : 5 ) = 100.

5. ( 5 x 5 ) x 5 - ( 5 x 5 ) = 100.

6. (-5 -5 -5 -5 ) x -5 = 100.