Oceans of Orcas

Here's your nightly math! Just 5 quick minutes of number fun for kids and parents at home. Read a cool fun fact, followed by math riddles at different levels so everyone can jump in. Your kids will love you for it.

Oceans of Orcas

July 23, 2017

Orcas are those beautiful black and white whales that we also call killer whales (but “orca” sure sounds nicer). Our fan Chandler M., who’s also a fan of orcas, asked us a great question: how many orcas are out there, and are there more in the Pacific or Atlantic Ocean? Orcas live all over the world, so it’s hard to count them. But scientists think there are at least 50,000 orcas. About 10,000 of those live in the Pacific, compared to only about 1,000 in the Atlantic near Norway. But the Antarctic really rocks: 25,000 killer whales there! As the biggest members of the dolphin family, they can stretch 26 feet long and weigh more than 6 1/2 tons. Even that “little” fin on their back is 6 feet tall. Do the math to find out how tiny you are compared to an orca!

Wee ones: Orcas are black and white. Can you find 2 things in your room that are both black and white?

Little kids: If you have 2 pet orcas and 3 pet dolphins, how many splashy pets do you have?  Bonus: An orca’s dorsal fin (on its back) stands 6 feet tall. How much taller than you is that? Find out your height in feet!

Big kids: If there are 25,000 orcas in the Antarctic, 10,000 in the Pacific, and 1,000 in the Atlantic, how many orcas is that? (Hint if needed: Instead of thousands, you can think of it as 25 chunks, 10 chunks and 1 chunk, and add them before turning into thousands.)  Bonus: How many 26-foot-long orcas would have to line up end to end to stretch 78 feet?

The sky’s the limit: If America’s (nearly) 350 million people share the world’s 50,000 orcas as pets equally, how many share each orca? (Hint if needed: What if it were just 50 million people? And how does this answer differ?)




Wee ones: Items might include the pages of a book, a newspaper, sneakers or socks.

Little kids: 5 splashy pets.  Bonus: Different for everyone…subtract your height in feet from 6.

Big kids: 36,000 orcas.  Bonus: 3 orcas.

The sky’s the limit: 7,000 people for each orca. If there were 50 million people (50,000,000), you’d have 1,000 people on each. But we’re talking about 350 million people, which is 7 times as much, so you need 7 times as many people sharing each one.

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About the Author

Laura Overdeck

Laura Overdeck

Laura Bilodeau Overdeck is founder and president of Bedtime Math Foundation. Her goal is to make math as playful for kids as it was for her when she was a child. Her mom had Laura baking before she could walk, and her dad had her using power tools at a very unsafe age, measuring lengths, widths and angles in the process. Armed with this early love of numbers, Laura went on to get a BA in astrophysics from Princeton University, and an MBA from the Wharton School of Business; she continues to star-gaze today. Laura’s other interests include her three lively children, chocolate, extreme vehicles, and Lego Mindstorms.

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