Sets and Relations Questions and Answers

Math
Sets and RelationsIs the set of rational numbers a group under the operation of addition?
Is the set of rational numbers a group under the operation of addition? If not, why not? Select all that apply.
A. Yes, it is a group.
B. No, it is not a group. There is no identity element in the set of rational numbers under the operation of addition.
C. No, it is not a group. There exist rational numbers a and b such that a + b*b+a.
D. No, it is not a group. There exist rational numbers a, b, and c such that (a + b) + c#a+ (b + c).
E. No, it is not a group. The set of rational numbers is not closed under the operation of addition.
F. No, it is not a group. There is at least one rational number that does not have an inverse in the set of rational numbers under the operation of addition.

Math
Sets and RelationsIn deciding whether or not to set up a new manufacturing plant, analysts for a popcorn company have decided that a linear function is a reasonable estimation for
the total cost C(x) in dollars to produce x bags of microwave popcorn. They estimate the cost to produce 10,000 bags as $5,340 and the cost to produce 15,000
bags as $7,710. Find the marginal cost of the bags of microwave popcorn to be produced in this plant. Round answer to the nearest cent.
A. $4.74
B. $0.47
C. $0.24
D. $47.40
E. $2.11

Math
Sets and RelationsFind all excluded values for the expression. That is, find all values of t for which the expression is undefined. If there is more than one value, separate them with commas.

Math
Sets and Relationscan someone please solve this using the rules of inference, implication, replacement! and this is a 54 line proof. i've posted this before too but im not getting the full 54 lines! 54 lines should be there!! Ill definitely give thumbs up!

Math
Sets and RelationsSolve the absolute value equation.
|2a + 10 = |3a-6
Select the correct choice below and, if necessary, fill in the answer box to complete your choice.
A. The solution set is.
B. The solution set is Ø.

Math
Sets and RelationsIf A = {x | x is an odd integer), B = {x|x is an even integer), C= {2, 3, 4, 5), and D={10, 11, 12, 13), list the element(s) of the following set.

Math
Sets and RelationsSolve the compound inequality. Graph the solution set and write it in interval notation. x≤-1 and x≥0

Math
Sets and RelationsIf A = {x|x is an odd integer), B = {x|x is an even integer), C = {2, 3, 4, 5), and D={15, 16, 17, 18), list the element(s) of the following set.

Math
Sets and RelationsSolve the compound inequality.
-3x≤-6 or 4x-1228
Select the correct choice below and, if necessary, fill in the answer box to complete your choice.
A. The solution set is
B. The solution set is Ø.

Math
Sets and RelationsConsider the two sets A = {n EN:n is both a perfect square and a perfect cube}
and B = {r € N:r = 0mod 7 or r = 1mod 7). If one wishes to prove A = B. then which of the
following describes a valid proof strategy? Select only one answer.
(a) Suppose z € A and prove r e B, and then suppose r&A and show r & B.
(b) Suppose z E A and prove z € B.
(c) Suppose z € An B and conclude re AUB.
(d) Suppose z € B and conclude z E A. and then suppose z E A and conclude a contradiction.
(e) Suppose z B and conclude z € A.

Math
Sets and RelationsIf a domestic car gets 14 miles per gallon on average,
how much carbon dioxide is emitted into the
atmosphere when the car travels 335 miles?
Express your answer rounded to the nearest tenth of a
pound of carbon dioxide.
lb of CO₂

Math
Sets and RelationsWrite the set using roster notation. Do not include repeats. Use the ellipsis button, if necessary. Give at least three terms before the ellipsis and at least two terms after the ellipsis.
Z= {x|x ε N and 150 <x< 400)
Z=

Math
Sets and RelationsIdentify the type of sampling used.
At a local technical school, five auto repair classes are randomly selected and all of the students from each class are interviewed. What sampling technique is used?
A. systematic
B. convenience
C. simple random
D. cluster
E. stratified

Math
Sets and RelationsDetermine the total number of subsets of the set of letters from the English alphabet (a, b, c,..., I).
The number of subsets is ___.

Math
Sets and RelationsDecide whether the statement is true or false.
ØE{0}
Choose the correct answer below.
A. True because (Ø) represents a set with one element, Ø.
B. False because Ø contains 0 elements so the only element of (Ø) is 0.
C. False because Ø contains no elements so nothing can belong to it. -
D. True because (Ø) is a subset of Ø.

Math
Sets and RelationsChoose which sets of ordered pairs satisfies an exponential function. Select two that apply
A {(-1,1), (0,0), (1,1), (2,4)}
B {(-1,-9), (1,9), (3,27), (5,45)}
C (-2,4), (-1,2), (0,1), (1,0.5)}
D (-1,1.5), (0,3), (1,6), (2,12)}