If a plane travels P miles in Q hours, how long will it take to travel R miles?

1 Answer
Dec 21, 2017

#(QR)/P#

Explanation:

There is an applied assumption of the plane travelling at constant speed. On this basis its speed is P/Q (distance/time).

The time to travel R miles is given by distance/ speed so this gives #R/(p/Q)=(QR)/P#