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Classify the following numbers as rational or irrational:
i) √23 ii) √225 iii) 0.3796 iv) 7.478478... v) 1.101001000100001...
√23 = √23/1 = p/q, but p is not an integer.
Hence √23 is an irrational number.
√225 = 15/1 = p/q, where p and q are integers and q ≠ 0.
Hence √225 is a rational number.
0.3796 is a rational number because it is a terminating decimal number.
7.478478... is a rational number as it is a non-terminating recurring decimal i.e, the block of numbers 478 is repeating.
v) 1.101001000100001 . . . .
It is an irrational number because it is a non-terminating and non-recurring decimal.
Classify the following numbers as rational or irrational: i) √23 ii) √225 iii) 0.3796 iv) 7.478478... v) 1.101001000100001...
NCERT Solutions Class 9 Maths Chapter 1 Exercise 1.3 Question 9
√23, 1.101001000100001... are irrational numbers whereas √225, 0.3796, and 7.478478... are rational numbers.
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