Do jet aircraft have a better glide ratio than propeller aircraft in general? If so, why?
&quot;Glide performance&quot; is measured by &quot;Lift-to-drag ratio&quot;:

In aerodynamics, the lift-to-drag ratio (or L/D ratio) is the amount of lift generated by a wing or vehicle, divided by the aerodynamic drag it creates by moving through air

When you look for examples you'll see that for the most part larger airliners do indeed have a more favourable L/D ratio

Boieng 747 = 17:1
Airbus A380 = 20:1
Cessna 172 = 11:1

As to why, that is the way they are designed. A good glide ratio is a favourable feature of an aircraft as less drag will imply better efficiency, and airlines are more concerned with efficiency than, for example, a training aircraft which might be more concerned with stability.
More information can be found here: How far can airplanes glide?