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A conditional probability problem |
2015-08-24 |
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Faustina. pose la question :
Please I have an exam tomorrow. And I have tried by best in solving this Question. An urn contains 10 white, 5 yellow and 10 black marble. A marble is chosen at random from the urn and it is noted that it is one of the black marble, what is the probability that it is yellow?
Penny Nom lui répond. |
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Four equations in 3 unknowns |
2015-08-23 |
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damien pose la question :
solve:
S x U - T = 44
T - U x S = 36
U + T - S = 7
U x U / S = 4
Penny Nom lui répond. |
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Reinforced steel mesh in a circular foundation |
2015-08-22 |
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Padmesh pose la question :
in a circular foundation we are laying a reinforced steel mesh . i.e., like chords in both ways. the circle diameter is 2.91m and rods are placed 0.1m spacing. so I want to find the number of rods present in that circle. here by I am attaching an auto cad drawing for your reference
Penny Nom lui répond. |
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Arrangements of the letters STRANGE |
2015-08-22 |
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Ravi pose la question :
In how many ways can the letters of the word STRANGE be arranged to that the vowels occupy only the old places.
Penny Nom lui répond. |
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A two digit number |
2015-08-21 |
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Cameron pose la question :
Write the 2 digit number that matches the clues.
My number has a tens digit that is 8 more than the ones digit. Zero is not one of my digits.
My number is ________.
Penny Nom lui répond. |
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The distance over a Quonset |
2015-08-20 |
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jane pose la question :
total base of hemisphere is 30 ft
apex height is 20 feet
what is total length over dome
Penny Nom lui répond. |
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A probability question |
2015-08-19 |
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Omar pose la question :
Hi my name omar ,
I have an exam tomorrow and i want answer of this question
Thank you
Q:the probability distribution function of a discrete random variable X is given by
P(X=x)=kx^3
For X=0,1,2,3
a)the value of the constant k .
Penny Nom lui répond. |
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20 golfers playing four rounds |
2015-08-17 |
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Paul pose la question :
I have a party of 20 golfers playing four rounds in fourballs.
I realise that everyone will have 7 players that they do not play
with, however I want to ensure that no one plays with the same
person twice and that the Captain plays with the 12 players of
his choice.
Victoria West lui répond. |
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Factor 2(x+1)(x-3)^2-3(x+1)^2(x-3) |
2015-08-13 |
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Bella pose la question :
The directions are the solve and factor the expression completely:
2(x+1)(x-3)^2-3(x+1)^2(x-3)
I was factoring out an (x+1) and and (x-3) however the answer showing in my book is different and I can't figure out what I'm doing wrong please help
Penny Nom lui répond. |
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Parallelogram area |
2015-08-04 |
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Nigel pose la question :
To find the area of a parallelogram you multiply the base by the height of the parallogram, the height being determined by an imaginary line drawn at right angles to the base. However if I made a parallelogram with joints at each corner and maipulated it to an upright position where the base and sides were at 90 degrees to each other,, I could then simply multiply the base times the height to get the area. Since the sloping side of the parallelogram does not vary in my imaginary jointed model, why can I not simply multiply the base by the sloping side to get the area in the same way that I multiply the base times the height of a square to find its area ? I cannot find the answer to this on the internet although I have searched.
Chris Fisher lui répond. |
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Rotating speakers through a 10 week schedule |
2015-08-03 |
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Timothy pose la question :
I want 15 students to speak 7 times each over the course of 10 weeks.
They each will have 5 minutes.
Thanks
Victoria West lui répond. |
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An oil field barrel |
2015-08-02 |
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Michael pose la question :
I have a storage tank that is 12' diameter x 22.5' high
it's capacity is 450 oil field barrels (42 gallon)
Which would hold 19,036 us gallons
I'm trying to find out how many inches it would take to make 1 barrel
I was able to get this far by using your volume calculator, but haven't been able to come up with the rest!
Thank you very much for your time, and I really appreciate this site and the tools you all have made available to everyone for free!
Hope to hear back from you soon and God bless you all!!
Penny Nom lui répond. |
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The length of a shadow |
2015-08-01 |
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maaz pose la question :
Hello
I am having trouble with this question:
Lizzie, who is 6 feet tall, stands in her driveway at night, exactly
24 feet from the base of a spotlight, and casts a shadow that is 12
feet long if her friend Hannah who is 5 feet tall decides to stand
next to lizzie how long will her shadow be?
Penny Nom lui répond. |
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The distance between two boats |
2015-07-26 |
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mohammad pose la question :
Two boats leave the same dock at the same time,one traveling due east at 10 mph and the other due north at 24mph,how many miles apart are the boats after 3hours ?
Penny Nom lui répond. |
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Scale |
2015-07-24 |
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Kenneth pose la question :
Hello:
Can you explain mathematically how the following scales become inches to feet?
For example, how does the scale of 1:160 become 1/16" = 1'?
(1:160) (1/16" = 1 foot) scale
(1:87) (1/8" = 1 foot) scale
I saw more of these different scale examples at the following:
http://www.oakridgehobbies.com/hobby-shop/modeling-in-scale-dimensions-f-a-q-s.html
I thank you for your reply!
Robert Dawson and Harley Weston lui répond. |
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