In mathematics, two variables are proportional if there is always a constant ratio between them. The constant is called the coefficient of proportionality or proportionality constant. If one variable is always the product of the other variable and a constant, the two are said to be directly proportional
The answer is letter d. The Fibonacci Sequence states to add the 2 previous number to get the next number starting with 1. So, 1 + 0=1, 1+1=2, 1+2=3, 2+3=5,3+5=8, 5+8=13, etc....
I added 13+21 to get 34. Then add 21+34 to get 55. Then add 34+55 to get 89.
