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let x be in ten s place and y in unit place.

so, number = 10x + y

As, 10x + y = 4(x + y) [number is 4 times the sum of digits]

10x + y = 4x + 4y

6x = 3y

y = 2x .... (eqn 1)

and, 10x + y = 2(x * y) [number is twice the product of the digits]

10x + y = 2xy

10x + 2x = 4x² [substituting value of y in eqn 1)

12x = 4x²

x = 3

y = 2x = 6

So, the number = 10x + y = 30 + 6 = 36