# Measure Twice, Cut Long

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.

# Measure Twice, Cut Long

August 27, 2013

In an earlier post I recommended seeking out mathematicians you already know and finding people your children can be introduced to who use mathematics in their jobs.

My Ace-in-the-Hole is Tracey Annable, owner of Windows, Walls & More a full service custom design, fabrication and installation company for home decor in Cincinnati, Ohio. Tracey is someone who is handy to have around, whether you are trying to figure out how to mitre a corner or help your kid work through a calculus problem. Before she started her business she spent a decade in the private sector estimating long-term natural gas supplies for our local energy company.

I asked Tracey what math tricks she uses in her business, figuring that someone with a Master’s degree in Mathematics might know a handy short cut or two for the more practical applications of math her business required. In her typical northeastern fashion she replied “none” and went on to say that she’ll sometimes spend whole days “doing the math” on a project before putting scissors to fabric.

[quote align=”center” color=”#999999″]I deal with fractions every day. You need to be able to do fractional arithmetic quickly and accurately because once you cut the fabric, you’d better be right. Remember, this isn’t origami – we aren’t cutting paper here.

When you have measuring tape on the fabric, the extra steps of using a calculator and going from fractions to decimals, doing the division then going back to fractions never ends in a whole eighth and takes up valuable time. I find it is more accurate for cutting to stick with the yardstick.

When I’m calculating intervals for roman shades or drapery pleats, I use the calculator to get me close then I switch to 8ths for the final calculations and do the math mentally. I think it’s really important that kids understand how to do these kinds of calculations in their heads.[/quote]

Indeed, each fabric has a different drape, weight and pattern repeat with some decorator fabrics costing upwards of \$150 per yard. Home decorator fabric generally comes in bolts between 54″ and 56″ but designers have to account for seam allowances (between 1/2″ to 5/8″) and trim. Matching the pattern from seam to seam (the pattern repeat) can often add to the complexity of a design layout.

Tracey reports that a recent box pleat window treatment with 13 1/16″ pattern repeat was particularly challenging.  She starts out with graph paper sketching ideas with customer specifications and actual detailed measurements. She might have a whole stack of graph paper drawings before she begins to actually work with the fabric.

So parents, the next time you embark on a home improvement project – from retiling a bathroom to creating a simple window treatment – engage your children in the planning, measuring and design piece. Build on the lessons learned in activities like Pizza Math  by having them create diagrams of their own. Little kids can begin to learn how to use graph paper to make “true-to-scale” renderings. Big kids can calculate material needs and learn some truisms of the trade in the process (like how even the common 2 X 4 is actually 1 1/2″ X 3 1/2″.)