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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 |
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Answer» Let the number be in the form of `10 X +y` , where x and y are the tens digit and the units digit respectively.Applying the first condition given in the problem, we GET `x +y =9 to (1)`Applying the SECOND 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 =4``therefore ` The number is 54. |
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