By definition we have to:
Rational number is any number that can be represented as the quotient of two whole numbers or, more precisely, an integer and a positive natural.
We then have the following number:
24/6
Rewriting we have:
24/6 = 4
We observe then that we also have a natural number because it belongs to the set:
ℕ = {1, 2, 3, 4, ...}
Whole number because it belongs to the set:
Z = {..., - 3, -2, -1,0, + 1, + 2, + 3, ...}
Real number because this set covers all the numbers:
Rational, irrational, whole and natural.
Answer:
The error of Damarcus is not to rewrite the number. Therefore, he did not realize that the number does belong to other sets of numbers