Question

The reciprocal of the smallest prime number is ___________.
a). 0
b). $${\displaystyle \frac{1}{2}}$$
c). 1
d). 2

Answer 1

HINT:- Let us firstly know about Prime Numbers, Composite Numbers, and Reciprocal.
PRIME NUMBERS: Prime numbers are the numbers that have only 2 factors: 1 and themselves. For example, the first 5 prime numbers are 2, 3, 5, 7, and 11.
COMPOSITE NUMBERS: Composite numbers are the numbers that have more than 2 factors. For example, the first five composite numbers are 4, 6, 8, 9, and 10.
RECIPROCAL: The reciprocal of a number is 1 divided by that number. So, for example, the reciprocal of 3 is 1 divided by 3, which is $${\displaystyle \frac{1}{3}}$$ . Reciprocal is also known as the multiplicative inverse.

Complete step-by-step solution -
Let us now solve the question.
We know that the number 2 is the smallest; and the only even prime number.
Therefore, we need to find the reciprocal of the number 2.
As mentioned in the hint provided above, the reciprocal of a number is 1 divided by that number.
Hence, the reciprocal of 2 will be 1 divided by 2, i.e. $${\displaystyle \frac{1}{2}}$$ .
Therefore, the answer of this question is $${\displaystyle \frac{1}{2}}$$, i.e. option (b).

NOTE:- Let us now know about the Additive identity and the Multiplicative identity.
ADDITIVE IDENTITY: Additive identity is a number, which when added to any number, gives the sum as the number itself. The Additive Identity of every number is 0, because adding 0 to a number does not change it.
MULTIPLICATIVE IDENTITY: Multiplicative identity is a number, which when multiplied to any number, gives the product as the number itself. The "Multiplicative Identity" is 1, because multiplying a number by 1 leaves it unchanged.