Diego scored 9 points less than 3 times the amount of points that Noah scored in the basketball game. If Noah scored 27 points, how many points did Diego score?

Sole with work in 10 years, the average number of hours of tv watched per week by teenagers dropped from 23.9 to 21.4. find the percent of change.

Ineed in figuring out this problem.

Atrain leaves little? rock, arkansas, and travels north at 90 kilometers per hour. another train leaves at the same time and travels south at 80 kilometers per hour. how long will it take before they are 680 kilometers? apart?