4 times the quantity of a number decreased by one is the same as two more than the same number. Find the number

The hard part is just making sense of what they are asking for.

4 times the quantity of a number decreased by one is just the expression:

4 * (x-1)

Where "x" is our mystery number.

Two more than the same number is just:

x + 2

Where "x" is our same mystery number.

They say that these two expressions are the same, so just set them equal to each other.

4 * (x-1) = x+2

4x - 4 = x + 2

3x - 4 = 2

3x = 6

x = 2

The mystery number is 2. Plug in 2 and you will see that it works!