With this information, you can calculate the quantity of knots 420 feet per minute is equal to.

¿What is the inverse calculation between 1 knot and 420 feet per minute?

Performing the inverse calculation of the relationship between units, we obtain that 1 knot is 0.24111569 times 420 feet per minute.

Which is the same to say that 420 feet per minute is 4.1473866 knots.

Four hundred twenty feet per minute equals to four knots. *Approximation

A knot is zero times four hundred twenty feet per minute. *Approximation