Let's define the variables:
- Let \( x \) be the number of months it will take Nicholas to collect the additional baseball cards.
- Nicholas currently has 95 cards and wants to reach a total of 200 cards.
The equation representing the situation is:
\[ 95 + 15x = 200 \]
Now we can solve for \( x \):
- Subtract 95 from both sides:
\[ 15x = 200 - 95 \] \[ 15x = 105 \]
- Divide both sides by 15:
\[ x = \frac{105}{15} \] \[ x = 7 \]
So the equation is \( 95 + 15x = 200 \) and it will take Nicholas 7 months to collect 200 baseball cards.