A rational number is any number that can be expressed as the quotient or fraction p/q of two integers, a numerator p and a non-zero denominator q.
Let us check each of them one by one:
I. π
π (Pi) is a famous irrational number. We cannot write down a simple fraction that equals Pi. The popular approximation of 22/7 = 3.1428571428571... is close but not accurate. Another clue is that the decimal goes on forever without repeating.
II.
120.5
we can write it in fraction as 1205/10
So it is a rational number
III. 12
We can write 12 as 12/1,
So it is a rational number.
IV.
7.25468
It can be written as 725468/100000
So it is a rational number.
V.
-56
We can write -56 as -56/1.
So it is a rational number.
VI.
2√
Since square root is involved, it is irrational.
Answer :
II, III, IV and V are rational numbers.
