Question: How do I assign a range of values to a name in Maple 15?

I hope this is the right place to ask, as the links for Maple Student Help were dead. I'm trying to assign a range of values to a name in order to solve questions about binomial distribution using variations of the function shown below:

The example given calculates the probability of at least 5 defective widgets being chosen from a quality control batch of 40, taken from a large consignment where 10% of the widgets are known to be faulty. Here the name r was orignally been assigned a value of four.  I'd now like to work out how to calculate for the probability of between 8 and 11 (inclusive) defective widgets being chosen (where I know the answer to be 0.415 or 4,15%), but I've no idea how to represent this in Maple 15. I assume it'll be something along the lines of ≥8 X ≤11, but nothing I try works. Can anybody help.