Write the interval (5,100] as an inequality and using set notation

The inequality notation with bracket 

[  ]  when we want to include the end value
(  ) when we don't want to include the end value

Interval (5, 100] means that 5 and 100 are the end values, we don't want to include the '5' but we want to include '100'

The inequality signs for not including end value is < and >
The inequality signs for including end value ≤ and ≥

(5, 100] = 5 < x ≤ 100