A fan has blades that spin at 50 revolutions per minute. the blades are 20 inches long. what is the angular velocity of the blades in radians per minute. round your answer to the nearest hundredth

314.16 radians per minute.

This problem is simply determining if you know what angular velocity is. Because of that, giving you the blade length is a trap. You're not looking for the tip velocity of the fan blades, just the angular velocity. And all you need for that is how fast the blades are spinning. 1 revolution will go through 2Ď€ radians. Since we have 50 rpm, the number of radians is:

2Ď€ * 50 = 100Ď€ = 100*3.14159 = 314.159 = 314.16 radians per minute.