the tens digit of a two digit number is twice the units digit. The sum of the digits is twelve. Find the original number.

1 answer:

4 0

X - tens digit
y - units digit

$x=2y\\
x+y=12\\\\
2y+y=12\\
3y=12\\
y=4\\\\
x=2\cdot4\\
x=8\\\\
10\cdot8+4=\boxed{84}
$

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