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The ten's digit of a two digit number is 1 more than 4 times the units' digit. if 63 is subtracted from the number, the order of the digits is reversed. find the number.

User Bill Dami
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1 Answer

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Let x be the digit in the tens place and y be the digit in the ones place.
so, the digit is xy

The ten's digit of a two digit number is 1 more than 4 times the units' digit.
x = 4y + 1

63 is subtracted from the number, the order of the digits is reversed
10x + y - 63 = 10y + x
9x - 9y = 63

x = 4y + 1 ------------ (1)
9x - 9y = 63 ---------- (2)

Sub (1) into (2)
9(4y + 1) - 9y = 63
36y + 9 - 9y = 63
27y = 63 - 9
27y = 54
y = 2 ------- sub into (1)

x = 4(2) + 1 = 9

x = 9, y = 2
The number is 92

User Geralyn
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