Let x be the tens and y be the ones digits.
The product of the number is then: 10x + y
The product is 1/2, so you need to multiply the product by 2 and the number:
10x + y = 2(x+y)
10x + y = 2x + 2y
Subtract 1 y from both sides
10x = 2x + y
Subtract 2x from
Both sides
8x = y
X has to be 1 , which would make y 8
The product number becomes 18
Since the product is 1/2, multiply by 2:
18 x 2 = 36
3 x 6 = 18
The answer is 36
