AVERAGE PRODUCT AND MARGINAL PRODUCT: 1  If the marginal is less than the average, then the average declines. 2  If the marginal is greater than the average, then the average rises. 3  If the marginal is equal to the average, then the average does not change. If the productivity of the marginal worker is equal to the average productivity of the existing workers, then the average does not change. 2  Marginal Less Than Average: Once the marginal product curve moves below the average product curve, then the average product curve declines.
Marine Engineer or Naval Architect Salary. (United States). Median pay for Marine Engineer or Naval Architects in the United States is around $84K annually. In the world of Marine Engineer or Naval Architects, total cash compensation can vary between $55K and $147K.arine Engineer or Naval Architect Salary. (United States). Median pay for Marine Engineer or Naval Architects in the United States is around $84K annually. In the world of Marine Engineer or Naval Architects, total cash compensation can vary between $55K and $147K.
The average, or mean, wages for marine engineers and naval architects were $38.10 per hour or $79,240 per year in May 2009, according to the Bureau of Labor Statistics (BLS).alaries ranged from $41,070 and less for the worst-paid 10 percent of marine engineers to $121,900 and up for the occupation's top 10 percent of wage earners.