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Question 893113: Maryum is twice as old as her youngest sister. The difference between their ages is 13 years. How old is her youngest sister?
Click here to see answer by algebrahouse.com(1659)

Question 893118: If |W|< 25 then
A) W < 25
B) W > - 25
C) W < 25 and W >-25
D) W≥ - 25
E) W ≤ - 25
Click here to see answer by erica65404(394)

Question 893107: What is the thickness, in inches, of pipe that has an outer diameter of inches and an inner diameter of 5 inches?
Click here to see answer by Alan3354(69443)

Question 893116: The point P(2, -1) lies on a cartesian plane. The point Q(a, b) is a reflection of P about the x-axis. What is the value of a?
Click here to see answer by Alan3354(69443)

Question 893106: The average speed of a car is 75 km/h. How many meters can the car travel in 20 minutes
A) 25
B) 250
C) 2500
D) 25000
E) None of these
Click here to see answer by Alan3354(69443)

Question 893104: What is the smallest integer u, for which 5u>625
A) 3
B) 4
C) 5
D) 6
E) None of these
Click here to see answer by Alan3354(69443)

Question 893109: How long will it take Jafar and Kadir working together to cultivate a filed which Jafar can cultivate alone in three hours and Kadiraline in six hours?
Click here to see answer by Jynald-(6)

Question 893112: The set of all integers values of w for which 5 A) {5,7,11,13}
B) {7,11,13, 17}
C) {4,5,��, 12}
D) {7,9,11,13,15,17}
E) None of these
Click here to see answer by jim_thompson5910(35256)

Question 893094: If |W| < 25 then
A) W < 25
B) W > -25
C) W < 25 and W > -25
D) W ≥ - 25
E) W ≤ - 25
Click here to see answer by jim_thompson5910(35256)

Question 899805: A says to B i am thrice as old as you are when i was at your age.If sum of their present ages is 60.Then find their present ages individually.
Note:the answer should be other than 45,15
Click here to see answer by ankor@dixie-net.com(22740)

Question 903091: I tried to prove this but I am lost on how to finish or am I done?
Proof:
∀ x, P(x) → R(x) (premise)
�R(k) (premise) (DeMorgan�s)
∴ �P(k) (universal instantiation)

Click here to see answer by solver91311(24713)

Question 905174: Write a two-column proof
Given:<1 and <2 form a linear pair
<2 and <3 are supplementary
Prove:<1 is congruent to <3
Click here to see answer by jim_thompson5910(35256)

Question 908872: I have a formula question.... m= c-ab Solve for a. Please try to respond quickly,I am having trouble with this problem.
Click here to see answer by josgarithmetic(39616)

Question 910335:
1. F ⊃ A
2. (~F v B)⊃ (A v D )
3. ~ A � ~ B / D
I can only use the first eight implications. Stuck please help! thank you
Click here to see answer by solver91311(24713)

Question 911180: For all integers n, n� � 3n +7 is odd.
Click here to see answer by Fombitz(32388)

Question 911219: Prove or Disprove: For all integers a and n, if (a divides n�) and a < n, then (a divides n).
Click here to see answer by richard1234(7193)

Question 911676: A
A horseshoe B
C horseshoe D
conclusion B or D
Click here to see answer by Fombitz(32388)

Question 911837: �1. [J v (N & T)]
2.� ~(~T -> S)�� /�� J

i need help solving this proof

Click here to see answer by guest567(1)

Question 911834: How does 5+(x+11)=x+(10+6)
Click here to see answer by rfer(16322)

Question 911871: a)
Prove the identity: cosh x - sinh x = e^-x
b)
Find the derivative of f(t) = csch t(1 - ln csch t)
Click here to see answer by ewatrrr(24785)

Question 911181: Prove or Disprove: For all integers a and n, if a│n� and a < n, then a│n.
Click here to see answer by richard1234(7193)

Question 912745: 1. Q horseshoe R
2. ~P
3. P v Q /R
4. 2,3,DS
5. 1,4,MP
the question is what fits in 4 and 5 i know 5 is R but cannot seem to figure out what 4 is. Thank you for your help!!
Click here to see answer by jim_thompson5910(35256)

Question 912958: prove the identity:
a)
cosh x - sinh x = e^-x
b)
find the derivative
f(t) = csch t(1- ln csch t)
Click here to see answer by ewatrrr(24785)

Question 914779: Prove- If a+b=c, then a=c-b
Click here to see answer by JoelSchwartz(130)

Question 914238: Hello,
Can you please help me in constructing a truth table for (not p) and q
This is so confusing I have no idea how to start
Thank you
Click here to see answer by Fombitz(32388)

Question 916774: Derive the conclusion from the given premise in the argument below
by utilizing inference rules:

C: A & C

--------------

P1: A & B

P2: B -> C
I have looked back in my notes and I do believe I need to use modus ponens, modus tollens, disjunctive syllogism, hypothetical syllogism or simplification. I am having a hard time trying to figure out what the next premise would be or how to go about even knowing the next premise.
Click here to see answer by jim_thompson5910(35256)

Question 917547: Construct a proof using any basic rules and replacement rules.
1.(A v F) horseshoe ~(B � ~G)
2.~(B horseshoe G)
3.~S horseshoe (~T horseshoe A)
4.T horseshoe F
The conclusion is ~(S horseshoe ~B)
I would appreciate the rest of the work for this problem as soon as possible, thanks!
Click here to see answer by Edwin McCravy(20054)

Question 918127: Why is 0! Equals to 1
Click here to see answer by Fombitz(32388)

Question 918545: if 1/8 of 9 number is 6, what is the number. answer is 128 but how?
Click here to see answer by Edwin McCravy(20054)

Question 919655: Translate the following argument into symbolic form,
Click here to see answer by richwmiller(17219)

Question 919654: Prove the following.
Click here to see answer by richwmiller(17219)

Question 922310: I cant figure out how to start this proof or complete it after I try
directions say to use the direct method
1. (BdotC)horseshoe D
2. B
3. Q horseshoe -(-CvD)
4. -Q triplebar T
/T
Click here to see answer by jim_thompson5910(35256)

Question 922639: Hi there!
I have been stuck on this one logic problem for the longest time. I am a junior in college and have seen my prof in her office hours every day for the last two weeks to get help, as well as paid tutoring services. It is not clicking for me, and I really need help with this one question:
1) ~H > (~T>R)
2) H v (E>F)
3)~T v E
4) ~ H * D /R v F
Click here to see answer by jim_thompson5910(35256)

Question 922936: how many oz of water do i add to 32 oz of 40% acid solution if i want a 20% solution and the steps you take to get it
Click here to see answer by ankor@dixie-net.com(22740)

Question 922936: how many oz of water do i add to 32 oz of 40% acid solution if i want a 20% solution and the steps you take to get it
Click here to see answer by Alan3354(69443)

Question 923409: Hi I have two homework problems that I cannot seem to quite get. In class and with my prof I can sort of get the answers but I cannot seem to get the correct answer here. The two that I am horribly stuck on are:
1) T
2) T > B
3) [(T * B) v K] > ~L
4) L v A /A * T

1) T * B
2) (T v M) > (C * A) /A v D

THANK YOU

Click here to see answer by jim_thompson5910(35256)

Question 923762: (2x+y) = 10x-4y. I need to find x and y, and the answer for both must equal 90. Of course, x and y is the same number-I need to find one number for x and one for y to make them both equal 90 degrees. Thank you!
Click here to see answer by richard1234(7193)

Question 924485: Prove algebraically that
(2n+1)^2-(2n+1) is an even number
for all positive integer values of n.
Please help :)
Click here to see answer by Fombitz(32388)

Question 924847: I need help deriving the conclusion using the 18 rules of inference.
1. C>(Dv~E)
2. E>(D>F) /C>(E>F)

Click here to see answer by jim_thompson5910(35256)

Question 925063: Hi, I was wondering if I could please have help on this proof?! We were introduced to two new rules that I am confused on!
1) B > D
2) B v D /D
Click here to see answer by jim_thompson5910(35256)

Question 925962: May I please, please have help on this problem! I have been trying it for hours, and do not know what to do with the triple bar!!!!
1. (B * D) ≡ ~K /~B > K
Click here to see answer by richard1234(7193)

Question 926787: if a man clear a plot of land at 3 hours, another man clear a plot of land at 5 hours and another man clear a plot of land at 7 hours, how many hours will it take 3 of the men to clear one plot of land
Click here to see answer by TimothyLamb(4379)

Question 926966: Can you please assist me with these problems? We are using the Rules of Inference and the Rules of Replacement and I am very confused about the Replacement Rules.Thank you very much!
#1-
Q=>(W * D) premise
Q=>W conclusion
#2-
I v (N * F) premise
I => F premise
F conclusion
#3-
P=>A premise
Q=>B premise
(P v Q) => (A v B) conclusion

Click here to see answer by jim_thompson5910(35256)

Question 927562: I do not know how to prove "For the function , prove that for all integers n>=0, " by using induction.
Click here to see answer by richard1234(7193)

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