let the number be xy then
x + y = 12
y - x = 2 ( because y > x)
adding we get 2y = 14 so y = 7
and x = 12 - 7 = 5
So the number is 57.
1/2(4+X)+2=16
2+(0.5 x X) + 2 = 16
4 + (0.5 x X) = 16
0.5 x X = 12
X = 24
idk if u understand my working out - message me if u dont
hope it helped tho :)