Answer:
Let X be the number.
Twice the number would be 2x
The difference between the two, would be subtraction, so you would subtract 4 from 2x
The equation becomes 2x-4 = 16
Now solve for x:
2x-4 = 16
Add 4 to each side:
2x = 20
Divide both sides by 2:
x = 20/2
x = 10
The number is 10.