At a high school, being a senior and being a sophomore are mutually exclusive events. The probability that a randomly selected student is a sophomore is 0.23. The probability that a randomly selected student is a senior is 0.21. What is the probability that a randomly selected student is a sophomore or a senior?

2people are trying different phones to see which one has the better talk time. chatlong has an average of 18 hours with a standard deviation of 2 hours and talk-a-lot has an average of 20 hours with a standard deviation of 3. the two people who tested their phones both got 20 hours of use on their phones. for the z-scores i got 1 for the chatlong company and 0 for talk-a-lot. what is the percentile for each z-score?

Find two consexutive odd integers such that the sum of their square is 650

What is the area of this figure. select from the drop down box menu to correctly complete the statement shows a rectangle 3in. by 16in. and a trapezoid center is 10 in. by 5 in. answers are 128 136 153 258