document.write( "Question 43839: In a 2 digit number , the units digit is twice the tens digit . If 27 is added to the number the digit inter-change their places . Find the number ? Pls help me i will be thankful \n" ); document.write( "

Algebra.Com's Answer #28955 by mszlmb(115) $\"\"$ $\"About$

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the unit's digit is twice the ten's digit; so the unit's digit can only be 2,4,6, or 8. [it cannot be 1 because 1/2 is .5 and you can't have a half in the ten's digit, can't be 3,5,7,9 because they're odd and require a half also, can't be zero unless ten's is zero but it's a 2 digit number so that can't be]
\n" ); document.write( "Accordingly, the ten's digit can only be 1,2,3,4. Can go no higher because twice 5 is more than 9 (highest 1 dgt number) and so forth.
\n" ); document.write( "the choices are 12,24,36, and 48. No more, as we have deduced, would fit the scenerio. This makes the problem relatively easier, we can use guess and check:
\n" ); document.write( "12+27=39 nope
\n" ); document.write( "24+27=51 nope
\n" ); document.write( "36+27=63 YES
\n" ); document.write( "48+27=75 nope\r
\n" ); document.write( "\n" ); document.write( "..THERE'S YOUR ANSWER! \n" ); document.write( "

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