Bedtime Math - Sample problems

Laura Bilodeau Overdeck ’91 makes up fun math problems for children through www.bedtimemath.org. Here is a sampling of problems from her site. 

1. Say Cheese … 

Satellites, the pieces of communications equipment that float miles above Earth, do all kinds of tasks. They carry our phone calls, our TV shows, and the photos we send to friends. Another job, though, is to take pictures of us. They’re actually snapping photos to make maps, track traffic patterns, and predict weather, but you could end up in those photos, too — and some of them are very high-resolution (showing lots of detail). If you’re going to grab your binoculars and watch one fly over, don’t go running out there in your underwear. 

Wee ones (counting on fingers): If Google Maps turns 7 years old this year, how much older or younger are you?

Little kids: We can see satellite photos of clouds just 3 hours after they were taken. If you look at a weather map at 4:00 in the afternoon, at what time did the clouds look like that? Bonus: These satellites go all the way around the Earth in about 90 minutes, or an hour and a half. If you see one at 7:30 tonight, when’s your next chance to run outside to pose for a photo? 

Big kids: The satellites that take pictures for Google Maps travel 423 miles up above Earth. How much farther is that than the distance from Boston to Washington, D.C. (393 miles)? Bonus: The high-res photos of cities, where they really can see you in your underwear, are often taken by other kinds of aircraft flying just 1500 feet above us. If your home is 30 feet tall, how many times higher do those planes fly overhead? 

Answers:

Wee ones: Different for everyone...

Little kids: 1:00 pm (local time). Bonus: 9 pm.

Big kids: 30 miles. Bonus: Just 50 times higher than your roof.

2. Getting Antsy 

If you’d like to have thousands of insects as pets, you can get yourself an anthill. If you prefer furry pets, you can get an anteater. Rest assured, you can’t keep both at once. The anteater, as its name would suggest, does in fact eat ants as a major part of its diet, along with termites. From its long snout shoots a skinny tongue that can worm its way deep into anthills and pull out a nice serving of bugs for dinner. And since an anteater can flick its tongue 150 times per minute , it can grab a lot of ants in just one brief sitting. Try slurping up your dinner that fast, and you’ll find you can barely keep up.

Wee ones: If your pet anteater eats 5 ants for breakfast, and you decide to try it yourself and you eat 3 ants, how many ants did the two of you eat together?

Little kids: If your anteater flicks its tongue 3 times and picks up 200 ants each time, how many ants did it eat? Bonus: If your anteater flicks its tongue 13 times in the next few seconds, takes a quick break, and then does 9 more tongue flicks, how many times did it flick its tongue?

Big kids: Anteaters visit about 200 bug nests in a day. If an anteater eats 35,000 ants in one day from 100 anthills, how many ants did it score from each nest on average? Bonus: If your pet anteater flicks its tongue 150 times in one minute, how fast can it flick it 15 times?

Answers:

Wee ones: 8 ants in total — yum.

Little kids: 600 ants. Bonus: 22 tongue flicks.

Big kids: 350 ants. Bonus: 1/10th of a minute, or a mere 6 seconds.

3. Happy Birthday, Harry! (from July 31, 2012)

Today is special because it’s Harry Potter’s birthday — as well as the birthday of his real-life author, J.K. Rowling. So it’s a good time to stop and marvel at the incredible numbers behind the Harry Potter books. The series has sold 450 million books , as compared to 220 million copies of Green Eggs and Ham, The Cat in the Hat, and all other Dr. Seuss favorites combined . It does show that if you’re ever thinking about writing a book, you can go ahead and think big.

Wee ones (counting on fingers): If you’ve read 4 of the 7 Harry Potter books, how many do you have left to read?

Little kids: Rowling took 17 years to write the Harry Potter books. How much longer is that than the time you've been alive? Bonus: If the last book came out 10 years after the first book, how long before the first book came out did she start writing them? 

Big kids: If the first 6 books were each turned into a 2 1/2-hour movie, while the last book spawned two 2 1/2-hour movies by itself, how many hours of Harry Potter movies were made? Mega-bonus: If the movies have grossed $900 million each on average worldwide ($900,000,000), how much did the 8 movies earn all together?

Answers:

Wee ones: 3 Harry Potter books left. 

Little kids: Different for everyone... Bonus: 7 years earlier (assuming she wrote continuously right up to the last one).

Big kids: 20 hours of movies. Bonus: $7.2 billion (or $7,200,000,000)!