Q33 of 44 Page 3

The sum of a two digit number and the number obtained by reversing the order of its digits is 99. If the digits differ by 3, find the number. (CBSE 2002)

Let the one’s digit be ‘a’ and ten’s digit be ‘b’


Given, sum of two-digit number and the number formed by reversing the order of digits is 99.


⇒ 10a + b + 10b + a = 99


⇒ a + b = 9


Also, digits differ by 3.


⇒ a – b = 3 or b – a = 3


Adding both equation


2a = 12 or 2b = 12


⇒ a = 6 and b = 3 or a = 3 and b = 6


Number can be 36 or 63

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