Question 326725
and hour and 12 minutes is equal to 6/5 hours or 1.2 hours, whichever you like 

working with. I will stick with fractions.

Since d=rt, we add the two distances together and between them they equal 384.

{{{(6/5)(r+20)+(6/5)r=384}}}

{{{r=150}}}

This means one is flying at 150 kph and the other at 170 kph.

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Again, d=rt. These types of problems are just variations on this small, yet useful, formula.

{{{500t+600t=5500}}}

{{{1100t=5500}}}

{{{t=5}}}