James bought a movie ticket and popcorn for $12.20.the movie ticket cost$8.45.use the equation c+$8.45=12.20 to find which size popcorn james bought. how much change did james get if he paid with a $20 bill?

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Acomputer store bought a program at a cost of $10 and sold it for $13. find the percent markup

Scores on a university exam are normally distributed with a mean of 78 and a standard deviation of 8. the professor teaching the class declares that a score of 70 or higher is required for a grade of at least “c.” using the 68-95-99.7 rule, what percentage of students failed to earn a grade of at least “c”?