Combined, two production lines can make 315 light bulbs in 1 hour. Production line A produces light bulbs 1.1 times faster than production line B. Using a rational equation, which of the following correctly calculates how many light bulbs can be produced in 1 hour using only production line A?

1 answer

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.