Stats Help for College-level Students

Probability

26. MCQ: A family center conducted research on carbohydrate consumption in the high school and found that 30% of all high school sophomores ate at least four candy bars a day. If 20 high school sophomores are selected at random, what is the probability that exactly 6 of these eat at least 4 candy bars a day? a) 0.300 b) ...continues

Probability: NBA (National Basketball Association) application

Probability questions on NBA. ONLY DO PROBLEM 1 and 2 from the four questions in the document. Problem 1 � Consider the NBA Data Set Given: A. What proportion of these players are less than 74 inches tall? B. Suppose a random sample of 25 of these players is taken and x is the number of players in the sample who are less ...continues

Multiple choice question about the mean of a distribution.

The number of cartoons watched by first graders on Saturday mornings is shown below: x, P(x) 0, 0.2 1, 0.2 2, 0.3 3, 0.15 4, 0.1 5, 0.05 The mean of this distribution is a) 1.9 b) 2.6 c) 2.4 d) 3.1 e) None of the above

True or false question about the area under a normal distribution curve.

True or false: The area under the normal distribution curve between z = 1.52 and z = 2.35 would be 0.0549.

Multiple Choice question about finding the mean from a normal distribution given standard deviation.

In a given normal distribution, the standard deviation is 14.4 and 8.27% of the distribution lies to the left of 60. What is the mean? a) 80 b) 40 c) 63 d) 72 e) None of the above

Multiple choice question about the area under a normal distribution curve.

What is the area under the normal distribution curve to the left of z = 0.87 ? a) 0.3078 b) 0.8078 c) 0.1922 d) 0.6922 e) None of the Above

Corresponding percentile of a z value

True or false. The z-value which corresponds to the 18th percentile is z = -0.92.

Probability: application of school children with asthma

A research company stated that 20% of missed school days are due to asthma. If a group of 400 school children are selected at random, what is the probability that fewer than 70 will miss school because of asthma? a) 0.1056 b) 0.0947 c) 0.1170 d) 0.4049 e) None of the above

Normal distribution, standard deviation and mean

If IQ scores on a Stanford-Binet Test are normally distributed with a mean of 100 and a standard deviation of 15, then about how many people in a randomly chosen million would be expected to score at 160 or above? (This was at one time the break off score for the "genius" designation.) a) 47 b) 32 c) 16 ...continues

Area under a normal distribution curve

What is the area under the normal standard distribution curve to the left of z = 0.87? a) 0.3078 b) 0.8078 c) 0.1922 d) 0.6922 e) None of the above