Abox is filled with 4 brown cards, 4 red cards, and 6 yellow cards. a card is chosen at random from the box. what is the probability that it is a brown or a yellow card? write your answer as a fraction in simplest form.

The first-serve percentage of a tennis player in a match is normally distributed with a standard deviation of 4.3%. if a sample of 15 random matches of the player is taken, the mean first-serve percentage is found to be 26.4%. what is the margin of error of the sample mean? a. 0.086% b. 0.533% c. 1.11% d. 2.22%