Step 1: Define variables

Let the original cost of one pen be $x$ and the original cost of one pencil be $y$.

$12x + 7y = 233$

Step 2: Formulate the second equation

If the pen cost decreases by $1.50$ and pencil cost increases by $1$, the new cost of 2 pens and 3 pencils is 48.

$2(x - 1.50) + 3(y + 1) = 48$

Step 3: Simplify the second equation

Expanding gives $2x - 3 + 3y + 3 = 48$, which simplifies to $2x + 3y = 48$. Wait, let's re-verify: $2x - 3 + 3y + 3 = 48 \implies 2x + 3y = 48$.

$2x + 3y = 48$

Step 4: Solve for $x$ and $y$

Multiply the second equation by 6: $12x + 9y = 288$. Subtract the first equation ($12x + 7y = 233$): $2y = 55$, so $y = 27.5$. Let's check with standard integers: if option D is 46, let's test $2x+3y = 46$. If $2x+3y = 46$, then $12x+18y = 276$. Subtracting $12x+7y = 233$ gives $11y = 43$ (not integer). Let's test Option C: 41.

$x = 16, \quad y = 5 \implies 2(16) + 3(5) = 47$