Dividing a Clock into Three Equal Parts
Date: 10/27/2002 at 12:36:09 From: Peter Hage Subject: Logic If you could help me with this fourth-grade problem I would be very grateful. They give you a picture of a clock with numbers 1-12 and ask, "Can you divide this clock into three parts using two lines and making all of the parts add up to the same number?" Here is my logic. I figured out that if you add up all the numbers of the clock, they add up to 78. Since 78 divided by 3 is 26, all the parts have to equal 26. My teacher suggested using toothpicks instead of erasing all of the pencil lines. I took her advice but it didn't help very much. Thank you in advance! - Peter
Date: 10/27/2002 at 13:13:09 From: Doctor Sarah Subject: Re: Logic Hi Peter - thanks for writing to Dr. Math. Your thinking about the sums of the numbers in the three different parts being 26 is excellent! Sometimes we get stuck on a problem like this because we think the lines have to start and end exactly where the numbers are. For this problem, we need to think about lines that start and end _between_ the numbers. You can see a start on this problem here: See if you can finish! - Doctor Sarah, The Math Forum http://mathforum.org/dr.math/
Date: 10/28/2002 at 18:33:40 From: Peter Hage Subject: Thank you (Logic) Thank you for your advice. It was very helpful and I have answered the question. I bet you will hear from me again in the future. - Peter
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