Question 717182
A two-digit number exceeds twice the sum of its digits by 7. Find the number if its tens digits is smaller than its units digit also by 7. 
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Equations:
10t+u = 2(t+u)+7
t = u - 7
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Rearrange:
8t - u = 7
t  - u = -7
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Subtract and solve for "t":
7t = 14
t = 2
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Solve for "u" using t-u = -7
2 - u = -7
u = 9
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Ans: The number is 10t+u = 29
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Cheers,
Stan H.
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