Question

a two digit no is four times the sum of its digit and twice the product of its digit

Answer 1

Let the digits be x,y

The number = 10x+y

Number = 4 times sum of digits

10x+y = 4(x+y)

10x + y = 4x + 4y

6x = 3y

x = 3y/6

x= y/2

Number = 2 product of digits

10x+y = 2 (xy)

(10 * (y/2)) + y = 2 * (y/2) *y

5y+y = y^2

6y = y^2

y = 6

x = y/2

x = 3

The number is 10x+y

=10*3+6

=30+6 = 36

The number is 36.