An education center offers a total of 400 math, physics and
chemistry courses. The ratio of the number of math to physics
to chemistry courses is 3:4:3.
The cost of a math class is $25 per class and the cost of a
physics class is $20 per class. If you took all 400 classes, it
would cost a total of $9,800. What is the price of each
chemistry class?

On a certain portion of an experiment, a statistical test result yielded a p-value of 0.21. what can you conclude? 2(0.21) = 0.42 < 0.5; the test is not statistically significant. if the null hypothesis is true, one could expect to get a test statistic at least as extreme as that observed 21% of the time, so the test is not statistically significant. 0.21 > 0.05; the test is statistically significant. if the null hypothesis is true, one could expect to get a test statistic at least as extreme as that observed 79% of the time, so the test is not statistically significant. p = 1 - 0.21 = 0.79 > 0.05; the test is statistically significant.