German for X rays where 'X'  means   'unknown'. In Europe X-rays are known as Roentgen rays.    X-Radiation is a form of electromagnetic radiation having a  wavelength of   0.01 to 10 nanometers.NS2: The name x-ray was applied to radiation in the same frequency as gamma radiation but which originate from a man-made source.
wikiHow to Calculate Gross Profit Margin. Gross profit is a fairly simple comparison of the cost of the goods your company sells to the income derived from those goods. Gross profit margin is the ratio of gross profit to total revenue expressed as a percentage.
Managers typically use gross profit to compute gross profit margin, also known as gross margin. This is a ratio showing the efficiency in which the business turns revenue into gross profit. The formula is gross profit divided by revenue for the period. Using the same numbers, you divide $210,000 by $420,000 and get .50. You multiply this by 100 to convert it to a percentage of 50. This is seemingly a strong gross margin, though you have to compare it to industry norms and prior periods to know for sure.