Percent composition, ppm, half life

Example: There are 20 students in a classroom, 12 of whom are males and 8 of whom are females. The percentage of males is 12 “out of” 20, or 60%. The percentage of females is 8 “out of” 20, or 40%. ... True or False. If a stock drops from $300 to zero, that is a 300 percent decrease. 3. A company has a 30 percent market share in the ... ................
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