Question 287083
the sum of the digits of a two-digit numeral is 9. The unit's digit is twice the tens' digit. Find the numeral.
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Let the number be 10t+u
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Equations:
t + u = 9
u = 2t
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Substitute for "u" and solve for "t":
t + 2t = 9
3t = 9
t = 3
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Since u = 2t, u = 6
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Number: 36
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Cheers,
Stan H.
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