On Die Hard, the riddle with the 3 and 5 gallon jugs. Always puzzles me even though they explain it really fast.

I used this in a Maths lesson recently.

You fill the 3 gallon jug and pour it into the 5 gallon. Then fill the 3 gallon jug again and pour it into the 5 gallon jug, leaving 1 gallon in the 3.

Then empty the 5, pour the 1 gallon into the 5 and fill the 3 again, pouring that into the 5 gallon jug (with 1 gallon in it) and there you go, 4 gallons.

As 3 and 5 are prime numbers there is actual number theory behind it, but it's boring so the explanation above will do.

Ahhhh

Whats that got to do with scunny trialists?!

Tree, the other place man!

Spideys hang out?

Yes!

Or, fill the 5gj, then use the 5 to fill the 3gj leaving 2 gallons in the 5, empty the 3gj and then pour in the 2 gallons from the 5gj, refill the 5 gj and use this to top up the 3gj from 2 to 3 gallons and you are left with 4 gallons in the 5gj
tis a sad life I lead posting this at 11.30pm

Let's hope recruitment firms don't do numerical tests if this was a problem

He applied for a job advertised last week, `Tree fellers wanted`, he went and said, " I can`t find 2 others to come with me!"

At another on a construction site, they asked him if he could operate a crane and he said "Yes",
then they asked if he could make tea and he said, " Jesus!, how big is the feckin pot?"!

I`m here all week

There was a computer adventure/detective game in the 1980s called Maupiti Island where at one point you had to solve a puzzle like this involving several containers (giant clamshells in this instance).
The solution would have been quite easy; the only thing was there wasn't actually a comprehensible definition of the friggin' problem in the first place.