SOLUTION: A number of two digits is such that twice the tens digit is 8 less than seven times the unit digit. When the d? A number of two digits is such that twice the tens digit is 8 less

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Question 1072305: A number of two digits is such that twice the tens digit is 8 less than seven times the unit digit. When the d?
A number of two digits is such that twice the tens digit is 8 less than seven times the unit digit. When the digits are reversed, the number is decreased by 9. What is the number?
Found 3 solutions by stanbon, MathTherapy, ikleyn:
Answer by stanbon(75887) About Me  (Show Source):
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A number of two digits is such that twice the tens digit is 8 less than seven times the unit digit. When the digits are reversed, the number is decreased by 9. What is the number?
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Let the number be 10t+u
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Equations:
2t = 7u-8
10t+u - 10u+t = 9
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Rearrange:
2t - 7u = -8
9t - 9u = 9
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2t - 7u = -8
2t - 2u = 2*9
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Subtract and solve for "u":
5u = 26
Note:: u is not an integer.
Pls check your post.
Cheers,
Stan H.
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Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

A number of two digits is such that twice the tens digit is 8 less than seven times the unit digit. When the d?
A number of two digits is such that twice the tens digit is 8 less than seven times the unit digit. When the digits are reversed, the number is decreased by 9. What is the number?
Correct answer: highlight_green%28matrix%281%2C3%2C+Original%2C+%22number%3A%22%2C+32%29%29

Answer by ikleyn(52780) About Me  (Show Source):
You can put this solution on YOUR website!
.
A number of two digits is such that twice the tens digit is 8 less than seven times the unit digit.
When the digits are reversed, the number is decreased by 9. What is the number?
-------------
Let the number be 10t+u
-----
Equations:
2t = 7u-8
10t+u - 10u+t = 9
------------------------
Rearrange:
2t - 7u = -8
9t - 9u = 9
--------------------
2t - 7u = -8
2t - 2u = 2
-----
Subtract and solve for "u":
5u = 10
-----
u = 2.

Then t = 3.

The number is 32.

Solved.