Suppose that the lifetime of tv tubes are normally distributed with a standard deviation of 1.1 years. suppose that exactly 20% of tubes die before four years. find the mean lifetime of tv tubes?

Aiden drives to school and back each day. the school is 16 miles from his home. he averages 40 miles per hour on his way to school. if his trip takes 1 hour, at approximately what speed does aiden drive home?

What are different types of statistical programs

How can you construct perpendicular lines and prove theorems about perpendicular lines