Answer: 1.15 is NOT an irrational number.
Step-by-step explanation: We are given to check whether 1.15 is an irrational number or not.
We know that a number in decimal form is
(i) rational, if the digits after the decimal are either terminating or repeating
and
(ii) irrational, if the digits after the decimal are non-terminating and non-repeating.
The given number is 1.15.
Here, the digits after the decimal are terminating, so the given number is rational, NOT irrational.
Thus, 1.15 is NOT an irrational number.