Can you FLIP your way to the right answer?

Your teacher places 100 quarters on a table in front of you.  You can't see the quarters because you are blindfolded, and you can't feel them because you are wearing gloves.  This means you can't tell if the quarters are heads or tails.  Fortunately, your teacher is nice and tells you that 20 of the quarters are heads, and the remaining 80 quarters are tails, but of course you don't know which are which because you can't see them or feel them through your gloves.

Your teacher makes you a deal.  If you can separate the quarters into 2 piles of any amount where each pile has the same number of quarters showing "heads", then you can keep all the quarters!

Can you figure out how to do this, and win all the quarters?

CLICK HERE TO SEE THE SOLUTION (scroll past the new problem)

SOLUTION FROM LAST WEEK

Since all you have is a balance scale, then you can't figure out the actual weights of anything.  You do know that the entire bag weighs 720g, and believe it or not, that's enough!  Here's how you do it:

Step 1)  Divide the bag of beads in half, which is easy to do with the balance scale.  You now have 2 piles of beads, each weighing 360g.

Step 2)  Take one of those piles and divide it in half using the balance scale once again.  You now have a pile with 360g, and 2 piles with 180g each.

Step 3)  Take one of the 180g piles and split it in half using the scale.  You now have a 360g pile, a 180g pile, and 2 piles with 90g each.

Step 4)  Now, simply combine the 180g pile with one of the 90g piles, and there you have it ... 270g of beads!