A scraper (pan hauler) moves 30 cubic yards per load, operates at 4 mph, and has an operating efficiency of 50 minutes per hour. If the material expands by 25%, how many cubic yards can be moved in one hour on a one-mile round trip?

A scraper (pan hauler) moves 30 cubic yards per load, operates at 4 mph, and has an operating efficiency of 50 minutes per hour. If the material expands by 25%, how many cubic yards can be moved in one hour on a one-mile round trip?

• A. 60 cubic yards
• B. 80 cubic yards
• C. 100 cubic yards
• D. 120 cubic yards

Answer: (B)

To determine how many cubic yards can be moved in one hour on a one-mile round trip, we start by calculating how long it takes to complete the trip. Since the scraper operates at 4 mph, we need to find out how long it will take to travel one mile. At 4 miles per hour, the time taken to travel one mile is 15 minutes (since 60 minutes divided by 4 miles equals 15 minutes). This round trip (one mile there and one mile back) takes 30 minutes to complete. With an operating efficiency of 50 minutes per hour, you can perform two round trips in one hour (each taking 30 minutes) and still have 10 minutes left for loading and unloading. For each round trip, 30 cubic yards are moved at full capacity. However, because the material expands by 25%, this needs to be factored in. When the material expands, the effective amount of material that can be loaded also increases. The calculation can be broken down as follows: 1. Each load, when taking into account the expansion, effectively is 30 cubic yards times 1.25 (to account for the 25% expansion) equals 37.5 cubic yards. 2

To determine how many cubic yards can be moved in one hour on a one-mile round trip, we start by calculating how long it takes to complete the trip. Since the scraper operates at 4 mph, we need to find out how long it will take to travel one mile.

At 4 miles per hour, the time taken to travel one mile is 15 minutes (since 60 minutes divided by 4 miles equals 15 minutes). This round trip (one mile there and one mile back) takes 30 minutes to complete.

With an operating efficiency of 50 minutes per hour, you can perform two round trips in one hour (each taking 30 minutes) and still have 10 minutes left for loading and unloading.

For each round trip, 30 cubic yards are moved at full capacity. However, because the material expands by 25%, this needs to be factored in. When the material expands, the effective amount of material that can be loaded also increases.

The calculation can be broken down as follows:

1. Each load, when taking into account the expansion, effectively is 30 cubic yards times 1.25 (to account for the 25% expansion) equals 37.5 cubic yards.

2