Exam 26: Introduction to Statistics and Probability

Company $x$ sold 127 computers in the year 1990. The number of computers sold by each of its five sales representatives in 1990 is shown in the table below: (a) Make a bar chart for the data. (b) Make a pie chart for the data.

We draw a ball from a bag that contains 4 red balls and 11 white balls. We replace the ball and draw another ball. What is the probability that both balls are white balls?

A snack company states that the weight of their chip bags is normally distributed with a mean of $180 \mathrm{~g}$ and standard deviation of $5 \mathrm{~g}$ . What is the probability of a randomly selected chip bag having a weight less than $170 \mathrm{~g}$ ?

The time (in minutes) taken to commute to work for 24 random people is given below: 5 7 8 8 10 10 12 15 15 15 18 20 20 20 20 22 24 24 25 25 25 26 27 28 Construct a frequency distribution for the data (include class, frequency, and cumulative relative frequency).

The amount of honey in a bee hive was recoded over several days Find the correlation coefficient and the least squares line.

The amount of hours spent on the computer per week for a sample of 40 random people is given below: 3 3 5 5 7 7 7 8 10 10 10 12 12 13 14 14 14 14 15 15 15 15 15 16 17 18 18 18 20 21 21 21 21 21 22 23 25 25 25 28 (a) Construct a frequency distribution for the data (include class, frequency, and cumulative relative frequency). (b) Draw a histogram for the distribution.

A bag contains five yellow jelly beans, six red jelly beans and eight blue jelly beans. If a jelly bean is drawn at random from the bag, what is the probability that it will be red?

Given the following data: Find the correlation coefficient and the least squares line.

A box contains twelve $5 \mathrm{amp}$ fuses and eight $10 \mathrm{amp}$ fuses. What is the probability of selecting a $10-$ amp fuse at random?

A certain coffee company has a prize promotion involving peeling a sticker from the top of your cup. If one in eight cups is a winner, what is the probability of winning 4 times if you buy 20 coffees? Express your answer to four decimal places.

In a certain parking lot, $45 \%$ of the cars have four doors, $16 \%$ of the cars are blue, and $4 \%$ of the cars have four doors and are blue. What is the probability that a car chosen at random will have either four doors or a blue color, or both?

From a random sample of 100 cars, the following data on the number tires that need replacing was found: NumberofTires Frequency 0 10 1 25 2 42 3 19 4 4 Find the weighted mean.

Rolling two standard six-sided dice, what is the probability of rolling a sum of 10 ?

In a sample of 850 ring bearings, the standard deviation is $0.02 \mathrm{~mm}$ . What is the Standard Error of the sample?

A factory kept track of its defectives (from random samples of 500 ) for 10 days and the following data was found: Find the values for the central line, and determine the upper and lower control limits.

We draw a ball from a bag that contains 5 red balls and 8 blue balls. We set aside the ball and draw another ball. What is the probability that both balls are blue balls?

Use the information below for questions. The average monthly rainfall (cm) in several cities in a certain province are: 11.3 29.6 16.3 31.4 29.2 14.5 16.9 25.8 21.3 32.7 15.3 13.5 25.2 22.5 18.6 14.3 26.9 22.9 -(a) Determine the range of the data. (b) Make an absolute frequency distribution using class widths of $2.5 \mathrm{~cm}$ . (c) Make a relative frequency distribution using class widths of $2.5 \mathrm{~cm}$ .

Consider the below set of lengths for questions: 123 422 566 329 247 296 245 522 362 593 229 475 357 227 489 326 -Find the range of the lengths.

If a die is rolled seven times, what is the probability of obtaining exactly three sixes?

Find the correlation coefficient and the least squares line for the following data: