Answer: 15.5 is a rational number.
Step-by-step explanation: We are given to check whether the number 15.5 is a rational or irrational.
We know that
a real number is said to be
(i) rational, if the digits after the decimal are either repeating or terminating.
(ii) irrational, if the digits after the decimal are non-repeating and non-repeating.
The given number is 15.5.
Here, the digits after the decimal are terminating.
So, the given number is a rational number.
Thus, 15.5 is a rational number.