The sum of the digits of a 2-digit number is 9. The number obtained by subtracting 9 from the number is equal to four times the number obtained by reversing it's digit. Find the number? answer = 81

The sum of the digits of a 2-digit number is 9. The number obtained by

1.	The sum of the digits of a 2-digit number is 9. The number obtained by subtracting 9 from the number is equal to four times the number obtained by reversing it's digit. Find the number? answer = 81
Answer» <html><body><p>Let the number be in the form of `<a href="https://interviewquestions.tuteehub.com/tag/10-261113" style="font-weight:bold;" target="_blank" title="Click to know more about 10">10</a> <a href="https://interviewquestions.tuteehub.com/tag/x-746616" style="font-weight:bold;" target="_blank" title="Click to know more about X">X</a> +y` , where x and y are the tens digit and the units digit respectively.Applying the first condition given in the problem, we <a href="https://interviewquestions.tuteehub.com/tag/get-11812" style="font-weight:bold;" target="_blank" title="Click to know more about GET">GET</a> `x +y =9 to (1)`Applying the <a href="https://interviewquestions.tuteehub.com/tag/second-1197322" style="font-weight:bold;" target="_blank" title="Click to know more about SECOND">SECOND</a> condition givent the problem, we get`10 x +y -9 = 10 y +x`` x-y =1 to (2)`Solving equations (1) and (2)We get `x = 5 and y =<a href="https://interviewquestions.tuteehub.com/tag/4-311707" style="font-weight:bold;" target="_blank" title="Click to know more about 4">4</a>``therefore ` The number is 54.</p></body></html>