Let’s use algebra to work this out.
Let x be the number.
I think of a number (x), increase it by 4, (x + 4) and double the answer (x + 4) x 2
the result is 20 more than the number (x + 4) x 2 = x + 20
(x + 4) x 2 = x + 20
Here can solve for x. First let’s expand the bracket.
2x + 8 = x + 20
Next, let’s take away x from both sides.
x + 8 = 20
Finally, let’s subtract 8 from both sides.
x = 12
The number is 12. :)
