1. Your question tells that the percentage of the red marble in the bag is 25%. So if a child chooses 4 marbles, the probability that he could get 3 red marbles is A.0.047
2.In your question the supplier has a stock of parakeets were 10% is blue, so the chance of the supplier to deliver 1 blue parakeet out of 3 is letter B.0.243
To the right: 0.51
to the left: -0.51
The answer to this question is the first item in the choices which is "The teacher should use the mean for both Amo and Javier" when computing and comparing their grades. The mean is the average grade while the median is the center of the grade. It would be wrong to apply median in computing their grades and it would be also wrong when the use two different methods when computing and comparing their grades.