The post Dance Like a Cockatoo appeared first on Bedtime Math.

]]>We know we can teach an animal to dance: we see it at the circus all the time. But do regular wild animals hear music and dance on their own, matching the beat? One scientist watched thousands of YouTube videos of animals “dancing” to music, and found 33 of them were in fact dancing. Of those 33 animals, 29 of them were birds! (The rest were elephants.) Another scientist tested one cockatoo named Snowball, playing the bird’s favorite song, “Everybody” by the Backstreet Boys.Whether he sped up the song or slowed it down, Snowball bopped to the beat about 1/4 of the time. There’s almost no chance that happened by accident, so that bird really can boogey.

*Wee ones:* If you clap to the beat 4 times, what numbers do you say?

*Little kids:* If the 5th dancing bird and the next 2 after that all liked rap music, what numbers were those next 2 birds? *Bonus:* If the 29 birds plus Snowball could all dance, how many dancing birds is that?

*Big kids:* If Snowball dances on the beat for 30 seconds and that’s just 1/4 of the song, how long is the song? *Bonus:* If the song “Everybody” is 3 minutes 44 seconds long, how many seconds would Snowball get to dance if she danced the whole song?

*The sky’s the limit:* If a bunch of birds and elephants hit the dance floor, and there are 4 more birds than elephants and 10 more elephant feet than bird feet, how many dancing feet are there in all?

Answers:

*Wee ones:* 1, 2, 3, 4.

*Little kids:* The 6th and 7th birds. *Bonus:* 30 birds.

*Big kids:* 120 seconds, or 2 minutes. *Bonus:* 224 seconds.

*The sky’s the limit:* 62 feet. If we have b birds and e elephants, then we have 2b bird feet and 4e elephant feet. Using those:

b = e + 4 , so 2b = 2e + 8

4e = 2b + 10

Substituting the first equation into the second, we get

4e = 2e + 8 + 10

So 2e = 18, and e = 9. There are therefore 9 elephants and 13 birds, giving us 36 elephant feet and 26 bird feet (which is 10 fewer than the elephant feet, like it’s supposed to be). That gives us 62 dancing feet in total.

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]]>The post Nelly’s Nose appeared first on Bedtime Math.

]]>Dogs love people, and are happy to play just about any game with us. Usually they like to catch, fetch, or just chase us across the yard. But here’s a dog who likes a different game: balancing things on her head. Nelly’s owners can give her just about anything — a toy plane, a light bulb, a carton of eggs — and she can hold it on her nose with no problem. Her owners have taken lots of pictures of her in these poses, and now Nelly’s nose is famous. Dogs also like to snack, but Nelly can balance a stack of potato chips on her nose, a grapefruit section, and a long loaf of bread without eating them. Nelly is a golden retriever, a breed (type) of dog that loves to fetch things. In Nelly’s case, looks like the owners are doing all the fetching!

*Wee ones:* If you can balance a flowerpot on your head for 4 seconds and Nelly can hold it for 6 seconds, whose falls first?

*Little kids:* If Nelly balances a blender for 5 seconds and a pint of ice cream for 7 seconds, how much longer did she balance the ice cream? Count up from 5 if it helps! *Bonus:* If she balances one right after the other, how long does the whole stunt take?

*Big kids:* If Nelly balances 2 stuffed animals, then 3 Lego cars, then 2 stuffed animals to repeat, what kind of toy is the 25th one she balances? *Bonus:* Of her first 50 toys in this pattern, how many would be stuffed animals?

*The sky’s the limit:* If we ask Nelly to balance a pineapple, a lamp, a juicebox, and a stack of toilet paper rolls in any order she wants, in how many orders can she balance them if the pineapple is always 3rd? (*Hint if needed:* What if the pineapple were always 1^{st}?)

Answers:

*Wee ones:* Your flowerpot.

*Little kids:* 2 seconds longer. *Bonus:* 12 seconds.

*Big kids:* A Lego car, because every set of 5 ends in a Lego car. *Bonus:* 20, since 2 out of every 5 are stuffed animals.

*The sky’s the limit:* Just 6 ways. Having the pineapple third is the same as always having it 1^{st}, so you can ignore it and find the different orders for the other 3 objects. You have 3 choices for the 1^{st} of those slots (L, J or T), and you have 2 choices for each of those choices, giving you 3 x 2; then you have just 1 item left, so it’s 3 x 2 x 1 = 6. If you want to write out the orders, they are LJT, LTJ, JLT, JTL, TLJ, TJL…and you can stick in a P in the 3^{rd} slot to see the real results.

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]]>The post How to Be a Juggler! appeared first on Bedtime Math.

]]>It’s International Juggler’s Day, a day all about the amazing act of juggling. It’s hard enough to catch a ball with one hand. But to toss a whole bunch of them into the air and catch them over and over with your 2 hands — that’s something else! There are two basic ways to juggle: throwing the balls, bananas or bean bags up and around in a circle, or throwing them across each other in an X. The more things in the air, the harder it is. The world record for the most balls juggled is 11, set by Alex Barron in 2012. He made 23 catches in a row! Meanwhile, the record for juggling flaming torches is 7, held by Anthony Gatto back in 1989. He also once juggled 3 running chainsaws, and made 94 catches in a row. The rest of us are better off practicing with bananas.

*Wee ones:* If you toss a banana, then a rubber chicken, then a banana again, then a rubber chicken…what do you juggle next?

*Little kids:* It’s easier to juggle odd numbers of things than even numbers. If you have 6 bananas, what are the 2 closest odd numbers? *Bonus:* If you have 8 flaming torches and your friends each want to practice with just 3, how many friends can you give 3 torches, and how many are left over?

*Big kids:* If Alex juggled 11 balls and made 23 catches, with the balls caught in the same repeating order, how many balls were caught more than twice? *Bonus:* If each ball weighed 6 ounces, how many pounds of balls was he throwing? (Reminder if needed: A pound has 16 ounces).

Answers:

*Wee ones:* A banana.

*Little kids:* 5 and 7. *Bonus:* 2 friends, with 2 torches left over, since you can give away 6 at most.

*Big kids:* Just 1, since the 11 balls went through 2 catches each to make the first 22 catches. *Bonus:* 4 pounds 2 ounces. They weigh 66 ounces total, and 64 ounces is the biggest multiple of 16 that’s still less than that.

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]]>The post Top 10 Pets appeared first on Bedtime Math.

]]>Lots of animals can make great pets: dogs, cats, guinea pigs, even flamingos if you have a pond. So what are the most popular household pets? There are two ways to answer this. If you count how many houses have one kind of pet or another, there are more dog houses than anything else — dogs win! But if you count animal by animal, a house can have more than one of an animal. In that case, cats and fish win. There are 81 million cats and almost 76 million fish, but 72 million dogs. Hey, as long as you’re putting fish food in the tank, you might as well have 20 fish in there, right? Rabbits, turtles, and guinea pigs all make the list, too, along with “livestock” like chickens and sheep. Wonder if anyone has one of each!

*Wee ones:* Who has the most legs, a flamingo, a fish or a dog?

*Little kids:* If you have 2 cats, 4 hamsters and a ferret, how many whiskery noses do they have? *Bonus:* If there are 20 houses on your street and all but 1 have a pet, how many homes have pets?

*Big kids:* 9 million homes have 76 million fish all together. If 8 million homes have just 1 fish, how many millions of fish are left for the rest? *Bonus:* 43 million houses have dogs, but just 37 million have cats. If 10 million houses in that whole set have both, how many have just 1 kind of pet?

*The sky’s the limit:* Say all the neighbors on your street have pet hamsters, turtles, and penguins. If the hamsters and turtles add up to 16, the turtles and penguins add up to 10, and the hamsters and penguins add up to 8, how many of each do you have?

Answers:

*Wee ones:* The dog, which has 4 legs.

*Little kids:* 7 noses. *Bonus:* 19 houses.

*Big kids:* 68 million fish. *Bonus:* 60 million homes (33 m dog homes and 27 m cat homes).

*The sky’s the limit:* 7 hamsters, 9 turtles, and 1 penguin. If you drop from 10 total to 8 total when you change from turtles-and-penguins to hamsters-and-penguins, there must be 2 more turtles than hamsters. They add up to 16, which means if the turtles dropped by 2, they’d be equal and add to 14. So there are 7 hamsters, which gives us 9 turtles. There are 10 pets when you add penguins to turtles, so there’s just 1 penguin.

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]]>The post Who Invented Hopscotch? appeared first on Bedtime Math.

]]>Can you hop? Jumping up and down on just one leg isn’t easy. Even bunnies don’t “hop” for real: they really jump off both back feet. So hopping is the big challenge in the game hopscotch. More than 1,000 years ago, soldiers in the Roman army got exercise by hopping through numbered squares drawn on the ground. Little kids liked the game so much that they copied it. They drew their own smaller squares, and that’s where hopscotch came from! In hopscotch you can write whatever numbers you like, throw rocks to block squares, and make up your own rules. So you can invent your own new game every time.

*Wee ones:** *What shapes do you see on this hopscotch board?

*Little kids: *If you write the numbers 1 through 8 in order on your hopscotch board, what number do you write before the 6? *Bonus: *If your hopscotch board has spaces 1 through 10, how many hops do you do if you land only on the odd numbers once each?

*Big kids: *If 6 people and their 6 pet bunnies start hopping, how many feet are hopping all together?* (Remember: *bunnies hop on 2 feet, but we don’t!) *Bonus:* If you number 1 through 12, and skip all the multiples of 4 as well as the non-4-multiple square your rock landed on, how many hops do you do to hop to the end and back?

*The sky’s the limit:* If a bunch of people and bunnies play hopscotch, and there are 8 players in total but 1 more bunny foot than people feet hopping, how many bunnies are playing?

Answers:

*Wee ones:* Squares and rectangles (both are 4-sided shapes), and at the end, almost a half-circle.

*Little kids: *The 5. *Bonus: *5 hops: on the 1, 3, 5, 7, and 9.

*Big kids: *18 feet. *Bonus: *16 hops, since you do 8 in each direction. You skip 4 squares: the 4, 8, 12, and rock.

*The sky’s the limit:* 3 bunnies, who hop on 6 feet while the 5 people hop on 5. You can start with 8 people on 8 feet, and each time you swap in a bunny for a person, the bunny feet go up by 2 while the people feet go down by 1, so the gap grows by 3. The gap started at +8 for the people and you need a gap of -1, so you have to change the gap by 9. You’ll need 3 swaps to do that, so 3 bunnies.

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]]>The post Orange You Glad You’re Not Round? appeared first on Bedtime Math.

]]>It’s funny how almost all fruits are round. Apples, oranges, watermelons, kiwis…why is that? Mother Nature may have a few reasons, one being that the fruit can roll away once it falls from the tree, and spread seeds for new trees. But then what about these 5-sided oranges from Japan? Don’t worry — the oranges don’t grow on the tree like that by themselves! The farmer puts a wooden frame around each one as it hangs from the branch. As the orange grows, it squishes itself into the corners and takes that 5-sided shape. The Japanese use this same trick to grow cube-shaped watermelons and other funny-shaped fruit…and none of it will roll off your plate.

*Wee ones:* Which has more sides, a square watermelon slice (4 sides) or this orange slice (5 sides)?

*Little kids:* What do you call a shape with 5 straight sides, like we see here? *Bonus:* It took the fruit growers 3 years to make this idea work. If they got it working in 2014, when did they start?

*Big kids:* By making cube-shaped watermelon, the Japanese can fit more pounds of watermelon on a shelf. If you have 4 rows of 6 cube watermelons, how many melons do you have? *Bonus: *If you have 20 5-sided orange slices side by side to make a full circle, so each one is touching the 2 it sits between, how many orange edges aren’t touching anything?

*The sky’s the limit:* If you stack a cube of 5 watermelons across, 5 front to back and 5 tall, how many watermelons are hidden inside, with no faces facing the air or the floor?

Answers:

*Wee ones:* The 5-sided orange slice.

*Little kids:* A pentagon. *Bonus:* In 2011.

*Big kids:* 24 melons. *Bonus:* 60, since each orange has 3 free edges.

*The sky’s the limit:* 27, since that inner cube will be 3 watermelons across, 3 deep and 3 tall!

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]]>The post A Not-So-Friendly Frog appeared first on Bedtime Math.

]]>If you want to have a pet frog, don’t get a really colorful one. That bright, tropical-looking frog might be a poisonous dart frog. Dart frogs come from Central and South America, and you can spot them from their bright greens, pinks and yellows. They’re also called poison arrow frogs, because long-ago people took the poison from the frogs’ skin and smeared it on the tips of their arrows. Even crazier, some scientists think the frogs stay poisonous by eating special insects, who turn poisonous by eating special plants! The most poisonous dart frog has enough poison in it to kill 10,000 mice…yikes. Those bright colors warn other animals like mice not to snack on them. So if you already have other pets, this might not be the best buddy for them.

*Wee ones:* Dart frogs come in bright shades of red, orange, yellow, green, and blue. How many frog colors is that?

*Little kids:* If you get 2 frogs of each of the 5 colors, how many poisonous pets do you have? *Bonus:* If you buy 2 frogs, twice as many poison beetles to help them out, and 5 poison plants for the beetles, how many poisonous things do you have?

*Big kids:* These frogs are only about 2 1/2 inches long. If you can fit 2 of them end to end on your hand, how long is your hand? *Bonus:* Some frogs jump 50 times their body length! If a 2 1/2-inch dart frog could do that, how far could it jump?

Answers:

*Wee ones:* 5 colors.

*Little kids:* 10 pet frogs. *Bonus:* 11 poisonous things (2 frogs, 4 beetles, 5 plants).

*Big kids:* 5 inches long. *Bonus:* 125 inches (over 10 feet!).

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]]>The post When Your Words Really Count appeared first on Bedtime Math.

]]>If you like your ABCs *and* your 123s, then Scrabble is the game for you. We celebrate it today on National Scrabble Day. You pick 7 little square letter tiles, which you keep secret from the other players. You line up the letters to make a word on the board so it crosses other words already there, like a crossword puzzle. The number on each tile tells you how many points you score for using it. Letters that are harder to use, like Q, X or Z, give you more points. Some spaces on the board double or triple the points for that letter, or even your whole word score! Best of all, if you use all 7 letters at once, called “racking,” you get an extra 50 points. You’ll be a winner if you’re good at both words and math!

*Wee ones:* How many letters does SCRABBLE have? (You can have a grown-up spell it for you while you count!)

*Little kids:* If you play the word DOG, the D and G each score 2 points, and the O scores 1. How many points do you score for DOG? Bonus: What if the D lands on a double letter space, so you double the D’s points…now how many points do you score?

*Big kids: *If you play the word WINNERS, the W is worth 4 points; the rest are 1-point letters. But if you get to triple the W and get 50 points for racking, how many points do you get? *Bonus:* What number can you spell with the letters VEYSTEN, and how many points is it? And what other words can you make? All letters score 1 point except the 4-point V and Y.

Answers:

*Wee ones:* 8 letters.

*Little kids:* 5 points. *Bonus:* 7 points, because you just added 2 again.

*Big kids:* 68 points: 12 for the W, 6 for the rest, and then 50. *Bonus:* SEVENTY, and it’s worth 4 plus 4 for the V and Y, plus another 5 for the other letters, plus 50 for racking. Other words, include NEST, NETS, VEST, VETS, SEEN, EYE, YES…and others!

The post When Your Words Really Count appeared first on Bedtime Math.

]]>The post A LOT of Extra Brothers and Sisters appeared first on Bedtime Math.

]]>Usually when a mom has a baby, just one baby comes out. Sometimes there are 2 babies, called twins; even more exciting is when there are 3 babies at once, called triplets…and the record is 8 babies at one time! They’re called octuplets. But our fans Alex and Jacob W. asked us, which animal of all has the most babies at once? For mammals, back in 2004 one mama dog had 24 puppies in one litter! But animals who lay eggs rack up bigger numbers. Among insects, a queen termite can lay 30,000 eggs in a day, adding up to around 165 *million* eggs in her life. Even crazier is that the cod (a fish), can lay 4 to 6 million eggs all in one batch. That makes it even harder to share with your brothers and sisters!

*Wee ones:* Fish, insects, reptiles and birds all lay eggs. How many kinds of animals is that?

*Little kids:* If you give 1 doggie treat to a mama dog and to each of her 4 puppies, how many treats do you give? *Bonus:* The most kittens in one litter is 19. How many more babies are in a dog’s litter of 24 puppies? Count up if it helps!

*Big kids:* A cod can lay up to 6 million eggs in 1 day. Can you “spell” 6 million in numbers? *Bonus: *If a termite lays 30,000 eggs a day all through June, how many eggs is that for the month? (Hint if needed: What would it be if she laid just 3,000 eggs a day?)

*The sky’s the limit:* If a queen bee in her life has 2,000 children who become queen bees, and each of those has 2,000 children, how many grandkids does the queen bee have?

Answers:

*Wee ones:* 4 kinds of animals.

*Little kids:* 5 treats. *Bonus:* 5 more babies.

*Big kids:* 6,000,000. *Bonus:* 900,000 eggs!

*The sky’s the limit:* 4,000,000 grandchildren. (2,000 kids x 2,000 kids for each of those).

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]]>The post Can Dogs Fly? appeared first on Bedtime Math.

]]>Flying a plane may look tricky, but even dogs are doing it now. Zoologist Mark Vette has trained 3 rescue dogs to fly a plane. Reggie, Shadow and Alfie can all fly a plane for up to 15 minutes. They can fly straight, on turns, and even in a figure 8. They first practiced on a “simulator,” which is like a video game: they learned to turn left when little blue lights lit up, right for the red lights, and straight for the white ones. After 4 months the dogs could then fly a real plane in the air. In the video the dogs fly very carefully, even though they keep turning to sniff the copilot and to eat doggie treats. Mark has also trained dogs to drive cars. We’ll see which dogs can get places faster!

*Wee ones:* If Mark has trained 5 driving dogs and 3 flying dogs, are there more driving dogs or flying dogs?

*Little kids: *If 1 dog flies 2 times this week and another dog flies twice as many times, how many times does the 2nd dog fly? *Bonus:* How many more times would that 2nd dog have to fly to reach 10 dog flights?

*Big kids:* If a people plane flies 600 miles an hour, and the dog plane flies that speed minus 200, plus 50, minus another 100, how fast is the dog plane? *Bonus:* If the dogs fly some 3-digit number of miles whose digits are all different, go from smallest to biggest from left to right, and add up to 7, how many miles must the dog have flown?

Answers:

*Wee ones:* More driving dogs.

*Little kids:* 4 times. *Bonus:* 6 more times.

*Big kids:* 350 miles an hour. *Bonus:* 124 miles. The only sets of digits that can add to 7 are 1, 1 and 5; 1, 2, and 4; 1, 3 and 3; and 2, 2 and 3. Only 1, 2 and 4 has 3 different digits.

And thank you John O. for this great news story!

The post Can Dogs Fly? appeared first on Bedtime Math.

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