Answer:
The other constraint for this situation will be:

Explanation:
The company takes 4 hours of labor to produce a mountain bike and 5 hours of labor to produce a road bike.
Here,
represents the number of mountain bikes per day and
represents the number of road bikes produced per day.
So, the total number of hours taken to produce
mountain bikes
and the total number of hours taken to produce
road bikes

Given that, the company has at most 300 hours of labor available per day. That means, the maximum number of hours should be 300.
So, the other constraint for this situation will be:
