The mean score of a placement exam for entrance into a math class is 80, with a standard deviation of 10. use the empirical rule to find the percentage of scores that lie between 60 and 80. (assume the data set has a bell-shaped distribution.)

Solve for x and y: 217x + 131y = 913; 131x + 217y = 827

Three baby penguins and their father were sitting on an iceberg 0.50.50, point, 5 meters above the surface of the water. the father dove down 4.74.74, point, 7 meters from the iceberg into the water to catch dinner for his kids. what is the father penguin's position relative to the surface of the water?

Which shows the graph of the solution set of 3y – 2x > –18?