Question -
Answer -
Let units digit of the number = x
and tens digit = y
Number = x + 10y
According to the given conditions,
x + 10y = 4 (x + y)
=> x + 10y = 4x + 4y
=> 10y тАУ 4y = 4x тАУ x
=> 3x = 6y
=>x = 2y тАж(i)
and x + 10y = 2xy тАж.(ii)
Substituting the value of x in (i)
2y + 10y = 2 x 2y x y
=> 12y = 4y2
=> 4y2 тАУ 12y = 0
=> y2 тАУ 3y = 0
=> y (y тАУ 3) = o
Either y = 0, but it is not possible because y is tens digit number
or y тАУ 3 = 0, then y = 3
x = 2y = 2 x 3 = 6
and number = x + 10y = 6 + 10 x 3 = 6 + 30 = 36