Big Ideas Math may have caused a search engine to land you on this page. In which case there is information on Fibonacci at the end of this page.
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Remember Bob who wanted to send a present to his Aunt? It will cost $1.20 times sum of the length, width, and height (measured in inches) of the package plus, they charge $3.00 flat fee on any order.
The formula was $3.00 + ($1.20)(length + width + height) = cost
What would it cost to send the package if the dimensions were width = 10", length = 15" and height = 5"?
Leonardo of Pisa was also known as Fibonacci. He wrote a book in 1202 called Liver Abaci which talked about the Fibonacci sequence. It's been around for a long time (as far back as 200 BC), but since I'm a westerner I will follow the western convention of claiming we thought of it.
The way I heard it, he used the sequence to predict the growth of rabbit populations. Which was an important source of food at the time. The sequence goes 0, 1, 1, 2, 3, 5, 8 ... With each number being the sum of the two previous numbers.
It doesn't really work for rabbit populations because of disease, predictors, and other factors (not a zoologist). It does occur quite often in nature. The spiral shape of sunflower seeds. Spiral shells show circles in circles whose dimensions are all Fibonacci numbers. And a host of other natural phenomena.