two people walk away from each other at an angle, one moving straight ahead at 6 ft per second, the other moving straight ahead at 4 ft per second. after 5 seconds, they are 24 ft apart. if they continue at the same angle and space, how far apart will they be after 1 minute?

well, 1 minute is 12 times as long as 5 seconds, so their separation will be 12 times as great.

All that nonsense about speeds and angles is useful if you want to use it, but it's irrelevant in this case.