Every once in a while, we’re driving down a road and have to stop to let an animal family cross. Hopefully you won’t have to stop and wait for 50 or more ducks to waddle across. That’s what we see in this picture, where a huge number of ducks take their merry time waddling across the street. We don’t know where the ducks are going or why, or how they stay in such a nice neat line. But we like seeing – and counting – them anyway.
Wee ones: Which has more ducks, a line of 8 ducks or a line of 6 ducks?
Little kids: If you and your pet duck take a walk, how many feet do you have together? Bonus: If every 3rd duck quacks when it reaches the street, starting with the 3rd duck (and no other ducks quack), will the 8th duck quack?
Big kids: If 37 ducks march in this parade, how many webbed feet are marching? Bonus: If every 3rd duck starting with the 3rd quacks when it reaches the street, and every 4th duck starting with the 4th wriggles its tail, which number ducks are the first 8 ducks to do an extra trick at the street?
Wee ones: The line of 8 ducks.
Little kids: 4 feet. Bonus: It will not quack — the 6th and 9th ducks will.
Big kids: 74 duck feet. Bonus: They will be the multiples of 3 and the multiples of 4, but remember, there’s overlap at 12! So the 3rd, 4th, 6th, 8th, 9th,12th, 15th and 16th ducks will either quack or wriggle (and both in the case of number 12).
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.