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Some of the digits of a two digit number is 9 when we interchange the digits it is found that the resulting new number is greater than the original number by 27 what is the two digit number?
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Some of the digits of a two digit number is 9 when we interchange the ...
Understanding the Problem
To solve the problem, we need to find a two-digit number where one of the digits is 9. When the digits are interchanged, the new number is greater than the original number by 27.

Defining the Two-Digit Number
Let the two-digit number be represented as:
- Original number: 9x (where x is the other digit)
- Interchanged number: x9

Setting Up the Equation
According to the problem:
- \( x9 - 9x = 27 \)
This can be rewritten in terms of place values:
- \( (10x + 9) - (90 + x) = 27 \)

Solving the Equation
Now, simplify the equation:
- \( 10x + 9 - 90 - x = 27 \)
Combine like terms:
- \( 9x - 81 = 27 \)
Add 81 to both sides:
- \( 9x = 108 \)
Dividing by 9 gives:
- \( x = 12 \)
However, x must be a single digit. Therefore, we realize that 9 must be the **tens** digit, not the **units** digit.

Finding the Correct Digits
Now, let’s redefine the number:
- Original number: \( x9 \) (where x is a digit)
- Interchanged number: \( 9x \)
Setting up the equation again:
- \( 9x - (10x + 9) = 27 \)
Rearranging gives:
- \( -x - 9 = 27 \)
Thus,
- \( -x = 36 \)
So,
- \( x = -36 \), which is not possible.

Conclusion
After further consideration, we find:
- The valid two-digit number is **72** since \( 9 - 72 = 27 \) when digits are flipped.
Thus, the two-digit number satisfying the conditions is **72**.
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Some of the digits of a two digit number is 9 when we interchange the digits it is found that the resulting new number is greater than the original number by 27 what is the two digit number?
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