#### Answer

$-3$

#### Work Step by Step

We let the unknown number be $x$.
Three times the unknown number is $3x$. Two less than three times the unknown number is $(3x-2)$.
Also, four times the number is $4x$.
The question states that two less than three times a certain number is one more than four times the number. This means that $4x+1$ equals $3x-2$.
Therefore, we write the following equation and solve:
$4x+1=3x-2 \\\\ x+1=-2 \\ x=-3$
Therefore, the unknown number is $-3$.