



 
Hi Pinar, Here is my picture of the wire after 4 bends. I have labeled the length of each section of wire and numbered the bends in red, calling the start of the wire bend zero. The length of wire used so far is $1 + 2 + 3 + 4 + 5 = 15$ centimeters. In the diagram notice that
Following this pattern
Hence the length of wire used after 6 bends is $1 + 2 + 3 + 4 + 5 + 6 + 7$ cm. What is the length of wire used after 7 bends? After 8 bends? How far do you need to go to get a length of 66 cm. It would be helpful if there were a nice formula for $1 + 2 + 3 + \cdot \cdot \cdot + n$ where $n$ is an integer. There is but it isn't necessary for numbers as small as you have in this problem. Penny  


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