Answer:
Option B ) √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 .
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