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Question 174390: Find a five-digit number in which the first digit is half the second, the third digit is half the fourth and the last digit is one more than the fourth and equals the sum of the first and third digits. The sum of all the digits is 20.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! Find a five-digit number in which the first digit is half the second, the third digit is half the fourth and the last digit is one more than the fourth and equals the sum of the first and third digits. The sum of all the digits is 20.
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let the digit pattern be abcde.
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Equations:
a - (1/2)b = 0
c - (1/2)d = 0
e = d + 1
e = a + c
a + b + c + d + e = 20
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Rearrange the equations:
a - (1/2)b + 0 + 0 + 0 = 0
0 + 0 + c - (1/2)d) + 0 = 0
0 + 0 + 0 + d - e = -1
a + 0 + c + 0 - e = 0
a + b + c + d + e = 20
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Use any method you know to get:
a = 3
b = 6
c = 2
d = 4
e = 5
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Number is 36,245
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Cheers,
Stan H.
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