Fibonacci

http://www.mcs.surrey.ac.uk/personal/r.knott/fibonacci/fibnat.html#bees

http://www.mcs.surrey.ac.uk/personal/r.knott/fibonacci/fibnat.html#bees

http://www.mcs.surrey.ac.uk/personal/r.knott/fibonacci/fibnat.html#seeds

http://www.mcs.surrey.ac.uk/personal/r.knott/fibonacci/fibnat.html#leaf
Fibonacci numbers are sequence that start with a number of term and it creates the value of term. You can use the formula F(n).For example: 1+1=2, 2+1=3, 3+2=5..etc. To solve a rectangle you use width/lenght equal to lenght/lenght+width and then you use proportion which is cross multiplying and then use the quadratic formula.Approximate the 3decimal is called Golden ratio.