In a large introductory statistics lecture hall, the professor reports that 55% of the students enrolled have never taken a calculus course, 32% have taken only one semester of calculus, and the rest have taken two or more semesters of calculus. the professor randomly assigns students to groups of three to work on a project for the course. what is the probability that the first groupmate you meet has studied
a) two or more semesters of calculus?
b) some calculus?
c) no more than one semester of calculus?

a) There is a 13% probability that a student has taken 2 or more semesters of Calculus.

b) 45% probability that a student has taken some calculus.

c) 87% probability that a student has taken no more than one semester of calculus.

Step-by-step explanation:

We have these following probabilities:

A 55% that a student hast never taken a Calculus course.

A 32% probability that a student has taken one semester of a Calculus course.

A 100-(55+32) = 13% probability that a student has taken 2 or more semesters of Calculus.

a) two or more semesters of Calculus?

There is a 13% probability that a student has taken 2 or more semesters of Calculus.

b) some Calculus?

At least one semester.

So there is a 32+13 = 45% probability that a student has taken some calculus.

c) no more than one semester of Calculus?

At most one semester.

So 55+32 = 87% probability that a student has taken no more than one semester of calculus.

$18 was the price of the t-shirt

step-by-step explanation:

when functions are first introduced, you will probably have some simplistic "functions" and relations to deal with, usually being just sets of points. these won't be terribly useful or interesting functions and relations, but your text wants you to get the idea of what the domain and range of a function are. small sets of points are generally the simplest sorts of relations, so your book starts with those.

step-by-step explanation:

state the domain and range of the following relation. is the relation a function?

{(2, –3), (4, 6), (3, –1), (6, 6), (2, 3)}

the above list of points, being a relationship between certain x's and certain y's, is a relation. the domain is all the x-values, and the range is all the y-values. to give the domain and the range, i just list the values without duplication:

domain: {2, 3, 4, 6}

range: {–3, –1, 3, 6}

(it is customary to list these values in numerical order, but it is not required. sets are called "unordered lists", so you can list the numbers in any order you feel like. just don't duplicate: technically, repetitions are okay in sets, but most instructors would count off for this.)

while the given set does indeed represent a relation (because x's and y's are being related to each other), the set they gave me contains two points with the same x-value: (2, –3) and (2, 3). since x = 2 gives me two possible destinations (that is, two possible y-values), then this relation is not a function.

note that all i had to do to check whether the relation was a function was to look for duplicate x-values. if you find any duplicate x-values, then the different y-values mean that you do not have a function. remember: for a relation to be a function, each x-value has to go to one, and only one, y-value.

state the domain and range of the following relation. is the relation a function?

{(–3, 5), (–2, 5), (–1, 5), (0, 5), (1, 5), (2, 5)}

i'll just list the x-values for the domain and the y-values for the range: