Harvest Your Future: Ace the 2025 Agricultural Engineering Exam!

The power tiller typically exhibits the highest internal rate of return (IRR) among the options listed due to several key factors. First, power tillers are relatively affordable and have lower initial investment costs compared to tractors and rice mills. They are highly efficient for land preparation, allowing farmers to save significant amounts of labor time and costs, and can often lead to increased yields by allowing timely planting.

Additionally, power tillers can be versatile in use, capable of performing multiple tasks such as tilling, planting, and even harvesting in some contexts. This multipurpose capability means that farmers can maximize their investment by using the tiller in different stages of crop production, thereby enhancing its economic viability. The quick return on investment due to workload efficiency and the ability to access small landholdings, where larger machinery may not be practical, further boosts the IRR.

In contrast, rice mills and tractors typically require a higher initial capital investment and often involve more operating costs, such as fuel and maintenance, which can reduce their overall return rates. Threshers, while useful for post-harvest processing, may not have the same level of wide usage or immediate economic impact as power tillers, which are critical to crop establishment and can directly affect the entire farming