NCERT Solutions for Class 8 Maths Chapter 1 Rational Numbers Exercise 1.2

Examples From Chapter 1 Rational Numbers

Ex. 1 Arrange in ascending order
2/5,1/3,−3/4,1/6

Soln: LCM of denominators 5, 3, 4, and 6 is 60.
Then 12/60, 20/60, (-15)/60, 10/60
Arranging in ascending order: −15/60,10/60,12/60,20/60
−3/4,1/6,2/5,1/3

Ex. 2 What is the multiplicative inverse of ∞.

Soln:  ∞ is the symbol used for undefined.
Therefore,

∞ =1/0

i.e. any non-zero number divided by zero is undefined or infinity.
For reciprocal of 10,

zero becomes the numerator and 1 becomes the denominator i.e. 0/1.
Hence,

zero divided by any non-zero number is zero.
Therefore,

the multiplicative inverse of  ∞ is 0.