July 4th is also known as Independence Day in America. It’s when we celebrate the birthday of the United States. But it took those first Americans a while to decide on a new flag. They tried out one with a snake on it – yuck – and another that looked so much like England’s flag that it confused everyone. Fortunately, Betsy Ross got us all under the same starry banner, and today, we’re going to the numbers behind her story – starting with 1776, of course!
BTM: What was it like growing up in the colonies?
Betsy: Crowded. For me, at least, since I had 16 sisters and brothers living in our house in Philadelphia. I was number 8 – talk about being a middle child! But I love my family, of course. And I never would have made history without my great-aunt Sarah, who taught me how to sew.
BTM: What else helped you make the first American flag, or at least the first one we all agreed on?
Betsy: Years of practice, but also, I was just in the right place at the right time. The Washingtons were members of the same church as I was. George started shopping at my upholstery store and we became friends – my husband John and I loved the Washingtons, even if Martha did get overly competitive during board game nights, and George could be picky about the width of the ruffles on his shirts.
BTM: So which took longer to make – Washington’s shirts or America’s Stars and Stripes?
Betsy: Well, George was a pretty tall guy, but the flag was still larger and took longer since it was a totally new creation. You know the saying measure twice and cut once? Seamstresses have a higher standard when it comes to careful measurement – I was seeing my measuring tape in my sleep! It took me about a month to make the flag after the Constitutional Congress asked me if I could do it. 7 identical red stripes, 6 identical white stripes, 13 5-pointed white stars.
BTM: If you don’t mind the interruption, aren’t 5-pointed stars hard to cut out of cloth?
Betsy: That’s what half of the Constitutional Congress thought too, but you can make a 5-pointed star with 1 snip of the scissors. It’s not magic, it just takes some geometric planning and folding. Your readers can learn my math-based method by watching this quick video, and they’ll be cranking out stars in no time.
BTM: And back to the whole flag – how big was it? How many stitches did it take?
Betsy: I made a 3-foot by 5-foot flag, which is the most common ratio for a rectangular flag for most countries. I used about 10 stitches per inch, and used double stitching to connect each stripe to the next, and to the blue square, so you can do the math! Here’s a hint: it was definitely over 10,000 stitches.
BTM: Wow, no wonder it took a month to make! What about those stars? How did you get them in a perfect circle centered in the “field of blue”?
Betsy: Oh, that was easy. I measured and marked the center of the blue square, then played around with the radius of the circle to see which arrangement and spacing of stars looked best. After that, I simply cut a piece of thread to the right radius length, pinned one end to the center of the square, and pulled the thread tight to draw the circumference of the circle of stars.
BTM: So if a kid wants to sew flags (or anything else) when they grow up, what kind of math do they need to know?
Betsy: Measurements, geometry, and all the operations. A quick example of how these skills help you plan a flag – if you have a 3 by 5-foot flag, and you want to fit 13 horizontal stripes into 36 vertical inches, then you know each stripe will need to be a little more than 2 and ¾ inches tall. Then you see that 4 red stripes and 3 white stripes will fit next to the blue square, and those stripes won’t need to be 5 feet long, so you can buy less red and white cloth. Basically, math helps you map out your flag before you cut any cloth or sew a single stitch, and then helps you adjust your plan as you go, too!
Feeling Patriotic? Let freedom ring with this Bedtime Math problem!
Image licensed by Ingram Publishing