Classify the following numbers as rational or irrational :

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Chapter 1

NCERT

Class 9

Mathematics

Solutions

9. Classify the following numbers as rational or irrational :

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Question:

Classify the following numbers as rational or irrational :

(i) √23 (ii) √225

(iii) 0.3796 (iv) 7.478478......

(v) 1.101001000100001.....

Answer:

(i) √23 is irrational number because 23 is not a perfect square.

(ii) √225 = √3×3×5×5

= 3 × 5 = 15

Hence, √225 is a rational number.

(iii) 0.3796 is terminating, so 0.3796 is a rational number.

(iv) 7.478478... is non terminating repeating decimal. So it is a rational number.

(v) 1.101001000100001... is non-terminating non-recurring decimal. So, it is an irrational number.

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(All Q's of this Chapter solved)

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