The sum of the digits of a 2-digit number is 8. If we add 36 to the number, the new number obtained is a number formed by interchange of the digits. What is the number?
Let the unit's digit of the number be $$y$$ and ten's digit be $$x$$
=> Number = $$10x + y$$
Sum of digits, $$x + y = 8$$ --------------(i)
According to question, => $$10x + y + 36 = 10y + x$$
=> $$9y - 9x = 36$$
=> $$y - x = \frac{36}{9} = 4$$ --------------(ii)
Adding equations (i) and (ii), we get :
=> $$(y+y)=(8+4)$$
=> $$y = \frac{12}{2}=6$$
Substituting it in equation (i), => $$x=8-6=2$$
$$\therefore$$ Number = 26
=> Ans - (A)
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