Our fan Aliza W. just asked us a great question: are there more girls or boys in the world? It seems like it should be about even, right? But the math gets more exciting than that. At birth, more boys are born: for every 100 baby girls, there are 106 baby boys. If you look at people of all ages, though, it evens out to about 1 boy for every girl. That’s partly because women live longer than men. In fact, if you look only at people 65 years or older, there are only 3/4 as many men as women. Remember, though, that for any age the boys are bigger than the girls. So if the whole world did a giant tug of war, the boys would have a good chance at winning.
Wee ones: Do you have more girls than boys in your family, or more boys than girls? How many of each?
Little kids: If a boy swings on the monkey bars, then a girl, then a boy…does a girl or a boy go 6th? Bonus: If there are 7 kids on the jungle gym and there’s 1 more boy than girl, how many of each are there?
Big kids: If 106 boys and 100 girls line up for tug-of-war, how many kids would that be in total? Bonus: If 19 more boys show up, how many more girls do we need to have equal numbers of each?
The sky’s the limit: If 800 200-pound men do tug of war against 1,000 women, how much do the women have to weigh to match the men’s total weight?
Wee ones: Different for everyone…count up your family!
Little kids: A girl goes 6th. Bonus: 4 boys, 3 girls.
Big kids: 206 kids. Bonus: 25 girls.
The sky’s the limit: 160 pounds each, since the men weigh 160,000 total.
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.