If a scraper operates only 50 minutes out of every hour, what is its effective operating time in one hour?

When a scraper operates for 50 minutes out of every hour, this means that during that hour, the machine is actively working for 50 minutes while the remaining 10 minutes may be spent on idle time, maintenance, or waiting for materials.

The effective operating time refers to the actual time that the equipment is functional and performing its intended task, which in this case is 50 minutes. Since the question specifically focuses on the operation of the scraper within that one-hour period, the correct answer is indeed that its effective operating time is 50 minutes.

This concept is essential in understanding machine productivity and efficiency, as it indicates how much time equipment is truly utilized versus how much time it is available. This can influence project planning, budgeting, and scheduling in excavation and grading tasks.