Question

Which number is Not a rational number?

A.-5 4/11
B. sqrt of 31
C. 7.608
D. 18.46...

Answer 1

sqrt(31) cannot be written as the ratio of two integers, and thus is irrational.

Answer 2

`√(31)`

Explanation:

A.
`-5 (4)/(11) =(-59)/(11)`

Since it in in p/q form so it is a rational number

B.
`√(31) =5.5677643.......`

Since it cannot be represented in the form of p/q . So, it is irrational number .

C. 7.608

`(7608)/(1000)`

Since it can be represented in p/q form . So, it is rational number.

D. 18.46...

18.4666.. Since 6 is repeating in decimal place . So, 18.46.. can be written in p/q form .

Hence Option B sqrt of 31 is not a rational number .