An epicyclic gear train is shown schematically in the adjacent

An epicyclic gear train is shown schematically in the adjacent figure. The sun gear 2 on the input shaft is a 20 teeth external gear. The planet gear 3 is a 40 teeth external gear. The ring gear 5 is a 100 teeth internal gear. The ring gear 5 is fixed and the gear 2 is rotating at 60 rpm ccw(ccw-counterclockwise and cw- clockwise)

The arm 4 attached to the output shaft will rotate at

T₂ = 20; T₃ = 40; T₅ =100

Given y –x	T₂	= 0
	T₅

⇒ x = 5y ....(1)
and y + x = 60 ....(2)
Solving (1) and (2), we get
y + 5y = 60
⇒ y = 10 rpm ccw