STA 122

The number of samples of five light-bulbs that can be selected from a lot of 20 bulbs is?

Let X be the number of borehole a company drill with a mean of 3 borehole per town in Nigeria .What is the probability that the company drill at least one borehole in a randomly selected town.

A random variable y has a pdf given below f(y)=k(y²+4) for 0

Let X be the number of boreholes a company drill with a mean of 3 borehole per town in Nigeria. What is the probability that the company drill at most one borehole in a randomly selected town?

Generally, ordinal variables are best displayed visually with:

Two events A and B are said to be INDEPENDENT if.......

When are events said to be collectively exhaustive ? This is when

Consider the experiment of drawing 1 card from a deck of 52 cards and observing whether or not the card is a spade. What is the probability of drawing a spade?

Find the co-  efficient of variation of a variable whose mean is 10 and variance is

Suppose the mean of scores obtained by students in a test is 14.If a mean of 217 is obtained when the scores are squared, what is the standard deviation of the scores.

A probability near 1 indicates an event is

There are two car factories, A and B .Each year ,factory A produces 1000 cars, of which 10 are lemons. Factory B produces 2 cars, which are lemons .All cars go to a single lot, where they are thoroughly mixed up. I buy a car .What is the probability that it is a lemon?

Measure of dispersion (or variability)includes the following except

Suppose that 24% of companies in a certain sector of the economy have announced plans to expand in the next year (and the other 76% will not).In a sample of twenty companies chosen at random drawn from this population, where n=20.Find the probability that the number of companies which have announced plans to expand in the next year will be three or more.

What is the class size of a class whose upper boundary is 10.5 and lower boundary is 4.5?

Suppose out of 10 objective questions in STA 122, five are to be answered. How many different sets of questions are possible?

The following list is a set of data ordered from smallest to largest:2,12,y,y,y,18,18,19.All values are integers and "y" is neither 12 nor 15.

I.The median and the first quartile cannot be equal.
II. The mode is 18
III. The median is 12.

Which of the following statement(s)is/are true about the data set?

Which of the following is an example of discrete variable?

Sample space has probability.

One of the following is NOT a measure under categorical variable

The General Social Survey asked respondents what region of the country they lived in at age 16.The level of measurement of this variable is:

If two variables are absolutely independent of each other the correlation between them must be,

There are two car factories, A and B. Each year ,factory A produces 1000 cars ,of which 10 are lemons. Factory B produces 2 cars, which are lemons. All cars go to a single lot ,where they are thoroughly mixed up. I buy a   is the probability it came from factory B?

Suppose that 24% of companies in a certain sector of the economy have announced plans to expand in the next year (and the other 76% will not) .In a sample of twenty companies chosen at random drawn from this population ,find the probability that the number of companies which have announced plans to expand in the next year will be precisely five.

If the probability of producing a defective screw is p=0.01, what is the probability that a lot of 100 screws will contain more than 2 defectives?

The first quartile divides a frequency distribution in the ratio

Given the set of data 1,5,6, 10,3 the range and the mean deviation respectively are

Sample space is itself an

Suppose that we have a samples pace S={E1,E2,E3},where E1,E2 and E3 denote the experimental outcomes and the following probability assignments are given for the sample events P(E1)=0.3,P(E2)=0.25,P(E3)=0.45.LetA={E1,E2}.Find P(A).

R² is the statistical notation for