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Question 145613: How does this work. Could I please get some help?
2. Select five random numbers between 70 and 100. Calculate the mean, median, mode, and midrange of these numbers. Based on your calculations, which measure of central tendency best represents these numbers?
Click here to see answer by kristina29(1)

Question 145891: What do you think about this px? Can you help me on this?
2. (5 pts)
Construct a frequency distribution of the ages that 25 randomly selected smokers started smoking:
26 26 25 17 16 16 14 17 21 16
16 18 17 15 15 19 16 17 22 15
19 17 16 27 16

Click here to see answer by Edwin McCravy(20054)

Question 145886: How can I do this. Any suggestions?
Construct a pie chart for the data and analyze the results. Draw a circle. Cut it into four slices with ratio 62, 18, 12, 8 � Results show most women work because they need the income for family of other purposes.
Click here to see answer by Edwin McCravy(20054)

Question 146000: could you help me; i am stuck. Please
a) A collection of all the objects to be studied is a sample false (population)
b) A subset or part of the subjects to be studied is a sample true
c) In a frequency distribution the class limits must overlap dont know � would say false
d) Pie charts are best used to plot numbers over a period of time false
e) A frequency distribution should have between 3 and 10 classes dont know -woiuld say true

Click here to see answer by stanbon(75887)

Question 146008: can you show mwe how to do this
7) (8 pts)
Construct a histogram and a frequency polygon for the following frequency distribution
Miles Number of Commuters
Class Frequency
0 - 24 4
25 - 49 10
50 - 74 11
75 - 99 5
100 �124 1

Click here to see answer by Edwin McCravy(20054)

Question 147503: symbolize the following argument and then use a truth table to determine whether the argument is valid or invalid.
1. Valerie will go out if and only if she does not have homework.
Valerie did not go out
Therefore, Valerie had homework.
p= (for me) Valerie will go out q= She does not have homework.
premise 1 p<--q premise 2 = p^~q conclusion = p <--> ^~q

Is that correct?
Click here to see answer by stanbon(75887)

Question 147603: Can someone help me construct this truth table? P->(P ->(Q ^ P)). Now, does this mean that first, you work the Q^P? or do you work the p-> which is inside the ( ) first. Then do you take the result of whichever is used and connect it with p-> which is oustide the ( ). Do that make sense. I'm confused too.
Click here to see answer by Edwin McCravy(20054)

Question 152200: Find the answer to the numbers 1-10 using three numbers 5,6,3.
Click here to see answer by oscargut(2103)

Question 154495: proove that square root of 2 is irrational!
Click here to see answer by AnlytcPhil(1806)

Question 156521: Adapted from Algebra and Trigonometry by P. Forester but I have a textbook by Holt
Prove the product of two negatives is a positive
(-x)(-y) = (-1*x)(-1*y) Identity
= (-1)[x*(-1)](y) distributive
= (-1)[-1*x](y)
= [-1*(-1)] xy
= 1*xy
= xy
therefore (-x)(-y) = xy
Click here to see answer by stanbon(75887)

Question 159824: Could I ask your help?
Lamps which cost $120 wholesale are sold for $192, at a profit of $6 per lamp. How many lamps were in the shipment?
9
10
11
12
13
Click here to see answer by vleith(2983)

Question 160240: I don't understand the logic proofs
not k
not l then h
j then k
h then j
therefore l
i understand modus tollens, modus ponens, law of sillogysm and law of contrapositives but not how they apply to a proof as long as the above.
i also don't understand how to do the proofs and reasons, the above has 7 of each

Click here to see answer by stanbon(75887)

Question 160091: Prove the argument:
1. p -> q
2. r \/ s
3. ~s -> ~t
4. ~q \/ s
5. ~s
6. (~p \/ r) -> u
7. w \/ t
therefore u /\ w
Click here to see answer by Edwin McCravy(20054)

Question 162438: problem 1f:
-(PvQ) -||- -P&-Q
Click here to see answer by vleith(2983)

Question 162437: Problem:
(P & Q) <=> ~(P -> ~Q)
Click here to see answer by Edwin McCravy(20054)

Question 162436: P v (Q & R) <=> (P v Q) & (P v R)

Click here to see answer by Edwin McCravy(20054)

Question 164160: 1. What is the maximum value for the function y= 1/3sin5x
a. 1/3
b. 1/5
c. -1/3
d. -5
2. if g(x)=4sin 5x+k, what is the minimum value of g(x)?
a. 4 - k
b. k - 5
c. k
d. k - 4
Click here to see answer by alicealc(293)

Question 167120: Are the multiples of two all prime, all composite, or both?
Click here to see answer by Earlsdon(6294)

Question 170241: find the exact value of
-2log2^4
Click here to see answer by Alan3354(69443)

Question 173249: I can't seem to get to solve this proof.
1. W->S
2. U->F
3. (S and F) -> O
4. ~O THEREFORE (~W v ~U)
Click here to see answer by jim_thompson5910(35256)

Question 174358: Translate this sentence into FOL: Notice that e is not in the same colum a either c or d.
Click here to see answer by stanbon(75887)

Question 174357: Translate this sentence into FOL: c is neither between a and b, nor in front of either of them.
Click here to see answer by solver91311(24713)

Question 174925: Present a formal proof in logic, using the laws of inference to reace the conclusion.
P-->A
G-->~R
A-->R
G v H
P
------
Therefore : H
Click here to see answer by EMStelley(208)

Question 175867: given two functions f(x) and g(x) show that the sum of their derivatives equals the derivative of their sum. ie d/dx f(x)+d/dx g(x)=d/dx (f(X)+g(x))
Click here to see answer by stanbon(75887)

Question 182391: I need help with constructing this proof. Can you help me?
Use the laws of inference to prove that the conclusion is true. Include statements and reasons in your formal proof.
24. Given: c-> b
a v ~b
c

Prove: a
Thank you, sincerely
freakertennis@yahoo.com
Click here to see answer by solver91311(24713)

Question 188797: I know that these two conjuncts are equivelant, but I do not know how to solve/show this!
prove ~(pvq) |- ~p &~q
Click here to see answer by jim_thompson5910(35256)

Question 188804: I cannot solve this: I can use: Transportation, Material Implication, Material Equivalence, Exportation, Tautology, Double Negation, Commutation, Association, Distribution, Demorgan's Theorem, Modus Ponems, Modus Tollens, Hypothetical Syllogism, Conjunstion, Simplification, Addition, Constructive Dilemma, Absorption and Disjuntive Syllogism.
1. 1.(T -> S) & (B -> D)
2. ~S v ~D
3. W -> (T & B) Therefore: W -> R
Click here to see answer by jim_thompson5910(35256)

Question 188809: I cannot solve this: I can use: Transportation, Material Implication, Material Equivalence, Exportation, Tautology, Double Negation, Commutation, Association, Distribution, Demorgan's Theorem, Modus Ponems, Modus Tollens, Hypothetical Syllogism, Conjunstion, Simplification, Addition, Constructive Dilemma, Absorption and Disjuntive Syllogism.
8. 1. p -> (q -> r)
2. ~ (q & ~r) -> s
3. s -> t
4. t <--> (q & ~s) Therefore: p <--> s
Click here to see answer by jim_thompson5910(35256)

Question 188807: I cannot solve this: I can use: Transportation, Material Implication, Material Equivalence, Exportation, Tautology, Double Negation, Commutation, Association, Distribution, Demorgan's Theorem, Modus Ponems, Modus Tollens, Hypothetical Syllogism, Conjunstion, Simplification, Addition, Constructive Dilemma, Absorption and Disjuntive Syllogism.
6. 1. (p v q) -> r
2. r -> (s <--> t)
3. s -> ~t Therefore: ~p v ~t
Click here to see answer by jim_thompson5910(35256)

Question 188805: I cannot solve this: I can use: Transportation, Material Implication, Material Equivalence, Exportation, Tautology, Double Negation, Commutation, Association, Distribution, Demorgan's Theorem, Modus Ponems, Modus Tollens, Hypothetical Syllogism, Conjunstion, Simplification, Addition, Constructive Dilemma, Absorption and Disjuntive Syllogism.
4. 1. p <--> q
2. p -> r
3. p -> (r -> s) Therefore: q -> s

Click here to see answer by jim_thompson5910(35256)

Question 188825: 1. p <--> q
2. p -> r
3. p -> (r -> s) Therefore q -> s

...so far I've tried this but I got stuck...
4. (p -> q) & (q ->p) 1 equivalence
5. p -> q 4 simplification
6. (q -> p) & (p -> q)4 Commutation
7. q -> p 6 simplification
8. q -> (r ->s) 7, 3 Hypothetical Syllogism
9. (q & r) -> s 8 exportation
10. (r & q) -> s 9 commutation
11. p -> (p & r) 2 Absorption
please help :(
Click here to see answer by jim_thompson5910(35256)

Question 188823: I can use: Transportation, Material Implication, Material Equivalence, Exportation, Tautology, Double Negation, Commutation, Association, Distribution, Demorgan's Theorem, Modus Ponems, Modus Tollens, Hypothetical Syllogism, Conjunstion, Simplification, Addition, Constructive Dilemma, Absorption and Disjuntive Syllogism.
10. 1. p -> (q <--> r)
2. ~q -> r
3. ~(q <--> s)
4. p -> s Therefore: ~p
Click here to see answer by jim_thompson5910(35256)

Question 188838: I saw that people can solve logic proofs on this site. I've looked everywhere for help. Could I get help with these two?
1. p v (q & r)
2. ~r
3. p -> (s -> ~t) /:. (therefore) ~(s & t)
AND
1. (p <--> q) -> s
2. ~(~r -> t)
3. ~q v ~s /:. (t v p) -> (~t & ~q)
I would write what I have so far but I know that it's really wrong and it just confused me.
Click here to see answer by Edwin McCravy(20054)

Question 188933: I cannot solve this: I can use: Transportation, Material Implication, Material Equivalence, Exportation, Tautology, Double Negation, Commutation, Association, Distribution, Demorgan's Theorem, Modus Ponems, Modus Tollens, Hypothetical Syllogism, Conjunstion, Simplification, Addition, Constructive Dilemma, Absorption and Disjuntive Syllogism.
1. p -> (q & r)
2. ~t -> (~r v ~s) Therefore: (p & s) -> t

I know that you must somehow get:
~p
~p v ~s Add
~(p & s) Demorgans
~(p & s) v t Addition
(p & s) -> t Implication OR
~t -> t
t v t Implication
t Tautology
t v ~(p & s) Addition
~(p & s) v t Commutation
(p & s) -> t Implication
But I cannot get the steps before these. Please help!
Click here to see answer by jim_thompson5910(35256)

Question 189101: I need to construct a proof using all of the rules: (ex. commutation, association, material implication, exportation, hypothetical syllogism, DeMorgans, Double Negation, Distribution, etc.)
1. (p <--> q) -> s
2. ~(~r -> t)
3. ~q v ~s Therefore: (t v p) -> (~t & ~ q)
Click here to see answer by jim_thompson5910(35256)

Question 188928: I cannot solve this: I can use: Transportation, Material Implication, Material Equivalence, Exportation, Tautology, Double Negation, Commutation, Association, Distribution, Demorgan's Theorem, Modus Ponems, Modus Tollens, Hypothetical Syllogism, Conjunstion, Simplification, Addition, Constructive Dilemma, Absorption and Disjuntive Syllogism.
1. ~(p <--> s)
2. (p v q) -> r
3. (t v ~s) -> (~s & ~r) Therefore: ~t & ~p
Click here to see answer by jim_thompson5910(35256)

Question 189186: ~(A or B) or ~(C or D)
(E or F) -> D therefore A-> ~E
Click here to see answer by jim_thompson5910(35256)

Question 188876: I am stuck, I do not know how to finish this.
1. (LvM).(Lv~S)
2. A->~L
3. A->(~MvS) :. ~A
|4. ~A assume
||5. ~MvS assume
||6. LvM 1, simp
||7. Lv~S 1, simp
||8. ~~(A->~L) 2, DN
Click here to see answer by jim_thompson5910(35256)

Question 188873: I need to solve using Transportation, Material Implication, Material Equivalence, Exportation, Tautology, Double Negation, Commutation, Association, Distribution, Demorgan's Theorem, Modus Ponems, Modus Tollens, Hypothetical Syllogism, Conjunstion, Simplification, Addition, Constructive Dilemma, Absorption and Disjuntive Syllogism.
1. (p <--> q) -> s
2. ~(~r -> t)
3. ~q v ~s Therefore: (t v p) -> (~t & ~q)
AND this is the other problem
1. p v (q & r)
2. ~r
3. p -> (s -> ~t) Therefore: ~(s & t)
Click here to see answer by jim_thompson5910(35256)

Question 189545: 1) I can only use the 8 rules of inference...
1. P v Q
2.(Q � ~R) → S
3. R → P
4. ~P / S
________________________
5.
6.
7.
8.
9.

Click here to see answer by jim_thompson5910(35256)

Question 189543: 6) I can only use the 8 rules of inference...
1. (~B � ~C) → (D → C)
2. ~B
3. C →B / ~D
________________________
4.
5.
6.

Click here to see answer by jim_thompson5910(35256)

Question 189542: 5) I can only use the 8 rules of inference.
1. C → (T → L)
2. ~L
3. ~E → C
4. L v ~E /~T
________________________
5.
6.
7.
8.
9.

Click here to see answer by jim_thompson5910(35256)

Question 189541: 4) I can only use the 8 rules of inference.
1. ~(S v R)
2. B → (S v R)
3. B v P
4. ~Q v B / P � ~Q
________________________
5.
6.
7.
8.
9.

Click here to see answer by jim_thompson5910(35256)

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