Let's define the production rates of the two lines.
Let \( r_B \) be the rate at which production line B produces light bulbs per hour. Then, since production line A produces light bulbs 1.1 times faster than production line B, we can express the rate of production line A as:
\[ r_A = 1.1 r_B \]
The combined production of both lines is given as 315 light bulbs per hour:
\[ r_A + r_B = 315 \]
Now, substituting for \( r_A \):
\[ 1.1 r_B + r_B = 315 \]
Combine the terms on the left-hand side:
\[ 2.1 r_B = 315 \]
Now, we can solve for \( r_B \):
\[ r_B = \frac{315}{2.1} \]
Calculating this gives:
\[ r_B = 150 \]
Now we want to find the production rate for production line A, which is:
\[ r_A = 1.1 r_B = 1.1 \times 150 = 165 \]
So, production line A can produce 165 light bulbs in 1 hour.
To summarize, the correct rational equation based on the problem's conditions is:
\[ r_A = 315 - r_B \]
And substituting in our earlier expression gives the solution that:
\[ r_A = 1.1 \cdot \left( \frac{315}{2.1} \right) \]
This shows that production line A can produce 165 light bulbs in 1 hour.