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Question 748822: In two digit number,the product of its digits is 18.if the places of the digits are interchanged,the number so formed is greater than the original number by 27,find the original number.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! In two digit number,the product of its digits is 18.if the places of the digits are interchanged,the number so formed is greater than the original number by 27,find the original number.
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Let the number be 10t+u
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Equations:
t*u = 18
10u+t - (10t+u) = 27
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Simplify:
t*u = 18
9u - 9t = 27
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t*u = 18
u - t = 3
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t*u = 18
u = t+3
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t(t+3) = 18
t^2 + 3t -18 = 0
(t-6)(t+3) = 0
Positive solution:
t = 6
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solve for "u":
u = t + 3
u = 9
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Ans: 10t+u = 10*6+9 = 69
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Cheers,
Stan H.
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