Probably because that's more or less the definition of "rational number": a number that can be expressed as a ratio of integers.
There are 44 positive integers less than 2,010 that have an odd number of factors.
There is no such number.
The set of positive integers less than 50 is finite (there are 49).The set of all integers less than 50 is infinite, because it includes an infinite number of negative numbers.
There are infinitely many of them: all integers which are less than 24.
In a list of positive integers less than 20.
In integers, that's 11,999
There are an infinte number of integers satisfying one or the other of the two inequalities.
-- When the number itself is bigger than ' 1 ' . . . yes. Always.-- When the number itself is less than ' 1 ' . . . . no. Never.-- When the number itself is ' 1 ', its square is also ' 1 ', so they're equal.
All positive integers less than or equal to 39 are whole numbers less than 40.
The odd integers greater than 5 and less than 15 are 7, 9, 11, and 13, a total of four of them.