Zara’s bicycle tire has a circumference of 1.5 m. If Zara travels 900 m on her bike, how many full rotations will her tire make?
, 2015
Pick one
Solution
The first fold creates 2 layers of paper. The second fold places 2 sets of 2 layers together, for a total of 4 layers of paper. Similarly, the third fold places 2 sets of 4 layers of paper together, for a total of 8 layers of paper.
That is, each new fold places 2 sets of the previous number of layers together, thereby doubling the previous number of layers.
The results of the first five folds are summarized in the table below.
Number of folds
0
1
2
3
4
5
Number of layers
1
2
4
8
16
32
After the sheet has been folded in half five times, the number of layers in the folded sheet is 32.
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