Question

The sum of the digits of a two digit number is 15. If the number formed by reversing the digit is less than the original number by 27, find the original number.

Answer 1

96

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ab=10a+b
ba=10b+a
a+b=15
ba=ab-27 --> 10a+b-10b-a=27 --> 9*(a-b)=27 --> a-b=3 --> a=b+3
a+b=15 --> b+3+b=15 --> b=6, a=9
ab=96