The women’s 500m speed skating event is scored as an average of two attempts at the distance. the quickest total score wins. in sochi the mean speed for the total speed across both races was 77.4 seconds, with a standard deviation of 1.3 seconds. what speeds represent the middle 50% of this distribution? choose the z-score closest to the percentage you are looking for if the exact percentage is not available. 76.5 to 78.3 seconds. -.67 to .67 seconds. 76.1 to 78.7 seconds. 77.4 to 78.7 seconds.

School has 204 sixth grade students. if the sixth grade is 30% of the total school, how many students are in the middle school?

If you have a set of parallel lines a and b cut by transversal x, if angle 1 = 167 degrees, what is angle 4 and why. also what is the measure of angle 5 and why? you need to use the names of the angle relationship and explain.

Arrange the steps to solve this system of linear equations in the correct sequence. x + y = -2 2x – 3y = -9 tiles subtract 3x + 3y = -6 (obtained in step 1) from 2x – 3y = -9 (given) to solve for x. substitute the value of x in the first equation (x + y = -2) to get y = 1. the solution for the system of equations is (-3, 1). x = -15 the solution for the system of equations is (-15, 13). add 3x + 3y = -6 (obtained in step 1) to 2x – 3y = -9 (given), and solve for x. x = -3 substitute the value of x in the first equation (x + y = -2) to get y = 13. multiply the first equation by 3: 3(x + y) = 3(-2) 3x + 3y = -6.