Long car trips have me staring at the horizon, mentally tracing and altering patterns and planning adjustments. Since I've become increasingly intrigued with European patterns, I often find myself trying to convert cms to inches in my head. I don't speak Metric system, much less *think* in metric. All I know is the rough translation: 2.5 cm is approximately 1 inch. Because dividing the number of cm by 2.5 is more than I can do while attempting to stay in my traffic lane, I switched to a simpler method: double the number of centimeters and divide by 5. (You remember in Algebra I, when they told you that you could multiply both sides of an equation by a common number? Well, finally here's a practical application for that nonsense....). Example, my new Onion pattern size chart says the back length is 41cm. Double the 41 to 82. Divide by 5. (Mentally - no cheating with paper and pencil.) Answer: 16 and 2/5...so it's a little less than 16-1/2". Checking my answer on a "bilingual" tape measure: 41 cm is about 16-1/4". Not perfect, but good enough for those times when I am being held captive without a calculator and a tape measure.
Yes, I know...it's basic math, and since my name is not Pythagoras, it's definitely a "recycled" idea. Anyone who laughs gets to balance my checkbook. |
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Thank you, Karla. I love this tip!!!
5/31/05 10:17 PM
I can truly appreciate your tip. I just got two Onion patterns and was trying to do a best guess on the numbers. Truly timely and helpful.
6/1/05 5:58 AM
I think I can do this! Someone else is driving, right?
6/1/05 7:28 AM
That's wonderful! My first really good math teacher used to say, "Use your head to save your feet." She enthusiastically encouraged us to find different, but mathmatically correct, ways to solve problems.
6/1/05 8:18 AM
Brilliant! I just may find myself actually doing some math in my ancient head! (Although probably not while driving -- 8^D)
6/1/05 9:45 AM
You can also multiply by 4 and divide by 10. So 41*4=164 164/10=16.4 It's the same result, but I think the math is slightly easier.
6/1/05 11:51 AM
hahahahaha......
6/1/05 5:37 PM
Karla, when I started sewing we used the imperial system but then Australia switched to metric. I always buy tape measures which have both side by side and which saves me from actually having to think! Sad, when I remember arithmetic was one of my favourite subjects!
6/2/05 3:43 AM
I need to do the conversion a lot because I use international pattern books. At first, I wrote a small conversion program and pasted the the chart on wall. Now, I simply look at my measuring tape(inch on one side, and metric on the other). Great tip though! I'll use it if I can't find my measuring tape :)
6/2/05 9:59 AM
Nice tip, I am going to tell it to my father. We live in Canada so, he learned imperial system and I learned metric system at school (Canada changed to metric system). He is always confused with metric.
6/2/05 12:28 PM
What a cool tip!
6/2/05 4:49 PM
Wow. This is such an easy way of doing the calculation. I have a tape in my bag which is only in cm's. I can be quite clever now!!
2/3/06 9:03 AM
Karla, don't speak about mathematics to me, because I'm absolutely figures analphabeth. Living in Europe, I'm using Burda WOF patterns and understand cm's. Browsing on the American quilting websites, I have to admit the only method I understand the inches is using one of my many inch tapes or google to inch/cm convertor.
4/15/06 6:31 AM