-10 belongs to the set of all integers denoted by Z.
1.18 is a number and number do not contain any sets (of any kind).
There are approx 5.709*10^45 possible sets of numbers that can be made out of the composite numbers in 1 and 200.
You can select 12 numbers for the first digit, 11 numbers for the second digit, and 10 numbers for the third digit; so 12*11*10 = 1320 sets of 3 numbers can be made out of 12 different numbers.
Infinity is not a number. There are different classes of infinity: The sets of natural numbers, integers, rational numbers all belong to the smallest class, with a cardinality of Aleph-null. The sets of irrational numbers and real numbers belong to the next higher level of infinity, with cardinality Aleph-One. Infinity can give rise to a very large number of apparent paradoxes - infinitely many of them?
there are 5 diffeerent sets Natural Numbers whole numbers integers rational numbers irrational numbers.
Irrational Numbers which are a subset of Real Numbers which are a subset of Complex Numbers ...
Rational numbers
Among other things, it belongs to the following sets: positive numbers; irrational numbers; algebraic numbers.
It can be element of: Rational numbers or Real numbers
Natural numbers.
real numbers, irrational numbers, ...
10 belongs to the set "natural numbers", but it can also belong to whole numbers, and rational numbers
17 belongs to the set of prime numbers
1.18 is a number and number do not contain any sets (of any kind).
The rational numbers, the real numbers and sets of higher order which contain the reals such as the complex numbers.
A set is just a way of describing numbers, and numbers can be described in more than one way. If set A is (for example) all positive prime numbers, and set B is all numbers between 0 and 10, then there are some numbers (2, 3, 5, and 7) that could belong to both sets.
-28 belongs to: Integers, which is a subset of rationals, which is a subset of reals, which is a subset of complex numbers.