there is a bag filled with 5 blue and 4 red marbles.
a marble is taken at random from the bag, the colour is noted and then it is replaced.
another marble is taken at random.
what is the probability of getting 2 that are different in colour?

You can find the constant of proportionality by finding the ratio of

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.

Solve the equation 1. x-3/4=2 4/52. -1/3x-11= -20 3. -12+5/7x= -19