Question

A fan has five equally spaced blades. Suppose you line up two fans directly on top of each other. What is the least number of degrees that you can rotate the top fan so that the two fans are perfectly aligned again?

A: 120 Degrees

B: 60 Degrees

C: 90 Degrees

D: 72 Degrees

Answer 1

Each blade is 360/5=72° apart from the next blade, so you would need to rotate the top fan by at least 72° to again line up with the bottom fan.