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DIGITS ISSUE

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DIGITS ISSUE

by francoisph » Wed Jun 16, 2010 4:17 am
Hi,

please any ideas?

if a two digits positive integer has its digits reversed, the resulting integer differs from the original by 27.
By how much do the two digits differ?


thks,
francois
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by selango » Wed Jun 16, 2010 4:18 am
10x+y=10y+x+27

9x-9y=27

-->x-y=3
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by amising6 » Wed Jun 16, 2010 4:31 am
if a two digits positive integer has its digits reversed, the resulting integer differs from the original by 27.
By how much do the two digits differ?


let two digit be xy = 10x+y (since has is at 10 th place)
reversing digit we have xy=10 y+x
(10x+y)-(10y-x)=27
9x-9y=27 dividing by 9 both side
x-y=3
so fdifference between two digit =3
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by francoisph » Wed Jun 16, 2010 4:35 am
why ? xy = 10x+y (since has is at 10 th place)

where 10X comes from please?
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by amising6 » Wed Jun 16, 2010 4:42 am
dude lets us take no 12
12 can also be written as 10.1 +2
so i have taken 2 digit as number as xy whixh is equal to 10x+y
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by selango » Wed Jun 16, 2010 4:43 am
If 2 digit number can be expressed as xy,Tenth digit will be x and expressed as 10x

for ex 75,x=5,y=5 will be 10(7)+5
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by francoisph » Wed Jun 16, 2010 4:59 am
ok guys

thks
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