To which rational number to which rational subset(s) does the following number belong? 15
1. Rational Numbers
II. Natural Numbers
III. Whole Numbers
IV. Integers

15 belongs to the set of natural numbers , whole numbers , integers & rational numbers.

Step-by-step explanation:

TO FIND :-

those subsets to which 15 belongs

FACTS TO KNOW BEFORE SOLVING :-

N = Set of all natural numbers

W = Set of all whole numbers

Z = Set of all integers

Q = Set of all rational numbers

It can be said that :-

N ⊂ W (∵ Whole numbers include all natural numbers along with 0)W ⊂ Z (∵ Integers include positive numbers i.e. whole numbers along with negative numbers.)Z ⊂ Q (∵ Rational numbers include all integers along with fractions.)

Hence , N ⊂ W ⊂ Z ⊂ Q

SOLUTION :-

Method 1 -

{15} ⊂ N (∵ 15 is an element of set N. {15} a singleton set & it can be called as the subset of N )

⇒ {15} ⊂ N ⊂ W ⊂ Z ⊂ Q

∴ 15 belongs to the set of natural numbers , whole numbers , integers & rational numbers too.

Method 2 -

A rational number is a number which can be expressed in "p/q" form where p,q are integers & q ≠ 0. 15 can also be expressed as . Hence, 15 is a rational number i.e. it belongs to the set of rational numbers.Natural numbers are the countable numbers. 15 is a countable number. So , 15 is a natural number i.e. 15 belongs to the set of natural numbersWhole numbers include all natural numbers as well as zero. 15 is a natural number. So , 15 is also a whole number i.e. 15 belongs to the set of whole numbers.Integers include the negative numbers as well as whole numbers. 15 is a whole number. So , 15 is also an integer i.e. 15 belongs to the set of all integers.

The first one is correct