1. The problem gives the equation $$y = -9x + 1830$$ where $x$ is the number of years since 1950 and $y$ is the average number of working hours per worker. 2. The Y-intercept is the value of $y$ when $x=0$. This means we look at the year 1950 (since $x=0$ corresponds to 1950). 3. Substitute $x=0$ into the equation: $$y = -9(0) + 1830 = 1830$$ 4. This means that in 1950, the average number of working hours per worker was 1830 hours. 5. Therefore, the Y-intercept represents the starting average working hours in the base year 1950 before any changes over time. Final answer: The Y-intercept means that in 1950, the average number of working hours per worker was 1830 hours.