Approval Process in Salesforce

An approval process also specifies the actions to take when a record is approved, rejected, recalled, or first submitted for approval. For example, when an employee creates a time-off request, have Salesforce automatically sends an approval request to the employee's manager.

[sani]

how to write in the step criteria if the discount rate is greater than 5 % and upto 10%
i wrote (field) (operator) (value)
opportunity : discount percent greater or equal to 5-10%
But i am getting invalid number .. how do i write this criteria ???