How to eliminate noise from a signal by averaging out n samples, where n is a value provided by means of constant block using simulink?

I am trying to measure duty cycle of a motor. Seems like signal has noise and I can't measure the duty cycle correctly. I want to consider every n samples and sum them up and divide it by n in order to calculate the average. This has to be done using basic simulink blocks since I don't have license for dsp tool box.