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. 150 light bulbs
2. 300 light bulbs
3. 165 light bulbs
4. 158 light bulbs

1 answer

Let x be the number of light bulbs produced in 1 hour using production line B.
Using the information given, production line A can produce 1.1x light bulbs in 1 hour.
Together, production line A and B can produce x + 1.1x = 2.1x light bulbs in 1 hour.
We are given that 2.1x = 315.
So, x = 315/2.1 = 150.
Therefore, production line A can produce 1.1*150 = 165 light bulbs in 1 hour.
The correct answer is option 3. 165 light bulbs.