Today from Bedtime Math: A Triple Bottle-Flip

People always tell us not to play with our food. But does that include drinks? Ever since this summer, lots of kids and grown-ups have gotten into bottle-flipping: tossing a spinning bottle of water into the air so it lands standing up. It's really hard to do, because the bottle has "momentum" and wants to keep moving after it touches the table. So people have to practice over and over to land that bottle perfectly. Well, our fans Matthew, Sean and Ryan D. took it to a new level: they sent this quick video of all 3 brothers flipping bottles, and all 3 bottles land! If you can, find a bottle and see if you can master this trick, too.

Wee ones: When you look at the bottom of a bottle from below, what shape do you see?

Little kids: If Sean flips the 1st bottle of water, then drinks the 2nd, then flips the 3rd, then drinks the 4th ... what will he do to the 8th bottle? Bonus: How many bottles has he flipped by then?

Big kids: If Ryan lands the bottle successfully on every 5th flip (starting with the 5th) and Matthew lands it on every 3rd flip (starting with the 3rd), on what flip will they both land their bottles at the same time? Bonus: After 30 flips, how many more bottles will Matthew have landed than Ryan?

Answers:

Wee ones: A circle.

Little kids: Drink it. Bonus: 4 bottles.

Big kids: On the 15th flip. Bonus: 4 more bottles, since Matthew will have landed 10 and Ryan will have landed 6.