Question

is .363636 irrational ?

Answer 1

because we cannot represent it in form

\[\large \dfrac{a}{b}\] where a and b are two rational numbers

Answer 2

Any terminating decimal number is rational.
If the numbr is exactly 0.363636, then it is rational.
A repeating, non-terminating decimal is also rational.
0.363636... (repeating 36) is also rational.