@Pooja Arora
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find the pairs of one-digit numbers whose sum is 8: \( (1,7),(2,6),(3,5) \) then the possibilities are 17,26 and 35 by trial and error we get 35

let the unit digit be x &tens digit be ythen original no.is10y +x.
and 1st equation is x+y =8
and 2nd equation is 10y+x+18=10x+y
then from eq.1 x=8-y
substituting the value of x in 2nd equation
10y+8-y +18=10(8-y)+y
9y +26=80-10y+y
9y+26=80-9y
9y +9y=80-26
18y=54
y=3
x=8-3=5
no.=10*3+5
35

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## Comments

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TopNewestThe number is 35.

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how??

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pls give me step by step procedure...

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\(x+y=8\)

\(10x+y+18=10y+x\)

Just solve these equations.

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let the unit digit be x &tens digit be ythen original no.is10y +x. and 1st equation is x+y =8 and 2nd equation is 10y+x+18=10x+y then from eq.1 x=8-y substituting the value of x in 2nd equation 10y+8-y +18=10(8-y)+y 9y +26=80-10y+y 9y+26=80-9y 9y +9y=80-26 18y=54 y=3 x=8-3=5 no.=10*3+5 35

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