QUESTION

The product of a fractional number and its multiplicative inverse is(a)0(b)1(c)number itself(d)none

Hint: Here, one can assume any fractional number. And, multiplicative inverse of that fractional number is basically its reciprocal fractional number.

In the question, it is talking about any fractional number in general. So, we can assume any fractional number to perform the above question.
Let us take a fractional number, say $\dfrac{x}{y}$
Here, x is in the numerator part while y is in the denominator part.
So, now we have to consider its multiplicative inverse. Multiplicative inverse is basically known as the reciprocal.
It means that the multiplicative inverse of any fractional number is its reciprocal.
In reciprocal, the number at the numerator part changes its position and goes to the denominator and the number at the denominator part changes its position and goes to the numerator part.
Therefore, the reciprocal of the fractional number, which we assumed above i.e. $\dfrac{x}{y}$ will be $\dfrac{y}{x}$
So, according to the question, we have to find the product of this fractional number and its multiplicative inverse.
Hence, the product of this fractional number and its multiplicative inverse $=\dfrac{x}{y}\times \dfrac{y}{x}$
And, it can be clearly seen that this product will be 1. That is $\dfrac{x}{y}\times \dfrac{y}{x}=1$
Therefore, the product of a fractional number and its multiplicative inverse is 1.
Hence, option (b) is correct.

Note: These types of the question generally don’t involve major calculations, else we have to look for the logic which is involved in the question and then, we have to solve it accordingly.