Rob8 the robot is good at dividing and adding.
Give Rob8 a number and he will divide it and add something to it over and over again.
For example, start with 37 and divide by 5 and add 1.
Rob8 will carry out these calculations:

Rob8 will keep going until the same number keeps appearing.

Try other starting numbers, does it matter what number you start with?
Divide by 4 instead of dividing by 5, what difference does that make?
Input any number and predict what will come out.
A little knowledge of the equivalence of decimals and fractions is needed.
Have a go