Chantel drew a picture of her dog on a piece of paper that is 12 centimeters long. She used a copy machine to enlarge her drawing. She used the 115% setting to make each new copy. She then used each new copy to generate the next copy, using the same copier setting. Enter a recursive formula that will give the length of each new copy. Answer is 1.15an-1. I just don't understand how to get that.

Given:
Piece of paper that is 12 cm long
Copied her drawing with 115% setting.
Uses each new copy to generate the next copy.

A recursive formula is a formula wherein each term is a function of the preceding term.

The recursive formula of the above scenario is 1.15n-1

n is the number of the copy.
1.15 is the 115% in decimal form
n-1 is the number of the preceding copy

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