PLLZZZ ANSWER 2.) There are three nickels, four dimes, and four quarters in your pocket. You randomly pick three coins and place them on a counter. The first coin is a nickel, the second is a dime, and the third is a quarter.

A..3/110,

b.8/165,

c. 1/64,

d.10/273

B.

Step-by-step explanation:

Total coins = 11 ( 3 + 4 + 4 = 11).

The probability of picking a nickel first = 3/11 ( 4 nickels out of 11 total).

The probability of picking a dime second = 4/10 = 2/5 ( 3 dimes out of 10 coins left).

The probability of picking the third coin as a quarter = 4/9 ( 3 quarters out of 9 coins left).

The probability of picking all three in that order = 3/11 x 2/5 x 4/9 = 8/165

The dean of students mailed a survey to a total of 400 students. The sample included 100 students randomly selected from each of the freshman, sophomore, junior, and senior classes on campus last term. What sampling method was used?

Solution: The sampling method used here is stratified sampling. Because the sample included the students from each of the freshman, sophomore, junior and senior classes.

Stratified sampling is is a probability sampling method and a form of random sampling in which the population is divided into two or more groups (strata) according to one or more common attributes and and a sample is selected by some design within each group.