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Probability and StatisticsQuestion and Answers: Page 1 |
Suppose that an urn contains 100,000 marbles and 120 are red . If a random sample of 1000 is drawn, what are the probabilities that 0,1,2,3 and 4 respectively will be red. What is the mean and variance? |
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If two fair dice is thrown twice, what is the probability of obtaining an even number |
If two fair dice is thrown twice, what is the probability of obtaining an even number |
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40 random numbers picked from 0 to 100. what is the probability that at least half of them has the range of 10. |
Calculate (((5+i)^4 )/(239+i)) Then Prove the Machin formula 4arctan((1/5))−arctan((1/(239)))=(π/4) |
Let 10≥x,y≥0 and x,y∈R Find a)P(x−2>y) b)P(x+2<y) |
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3 different integer numbers are chosen from 0 to 10. what is the probability that they form 1 Cluster 3 Clusters 2 Clusters A cluster is a set of numbers that has maximum range of 2. for example 0,1,2 forms only one cluster. 0,1,4 forms 2 {0,1} and {4}. 0,1,3 also forms 2 {0,1} and {1,2} |
3 numbers are selected randomly from 0 to 10 (Continuous). forming a new range. what is the probability that the new range is less than or equal to 2? new range = max-min |
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find integers x,y such that (x/(x−3)) −(4/(y^2 −45)) = (1/(100)) |
If the probability of A solving a question is 1/2 and the probability of B solving the question is 2/3 then the probability of the question being solved is |
Q) The collection A={12,13,15,18,23,24,25,26}& B⊆A if m,M ∈B ; m=min & M =max & nm=10k which number of B : 1)59 2)60 3)61 4)62 |
three points are randomly selected on a circle to form a triangle. 1) find the probability that the center of the circle lies inside the triangle. 2) find the probability that the triangle is an acute triangle. |
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n married couples are invited to a dance party. for the first dance n paires are radomly selected. what′s the probability that no woman dances with her own husband? 1) if a pair must be of different genders. 2) if a pair can also be of the same gender. |
Two ships have the same berth in a port. It is known that the arrival times of the two ships are independent and have the same probability of docking on a Sunday (00.00−24.00) If the berth time of the first ship is 2 hours and the berth time of the second ship is 4 hours, the probability that one ship will have to wait until the berth can be used is □ ((67)/(144)) □ ((67)/(288)) □ (1/4) □((33)/(144)) |
It is known that a balanced 6−sided dice originally had 2,3,4,5,6 and 7. The dice wre thrown once and the result was observed. If an odd numbers appears, than the number is replaced with the number 8. However, if an even number appears , the number is replaced with the number 1. Then the dice whose dice have been replaced are thrown again, the probability of an odd dice odd dice appearing is □ (1/3) □ (2/3) □ (1/2) □ 1 |
(1/1) (((20)),(( 0)) ) +(1/2) (((20)),(( 1)) ) +(1/3) (((20)),(( 2)) ) +...+(1/(21)) (((20)),((20)) ) =? |
Let cardE=n , and the set of parts S={(A,B)∈P(E)×P(E) / A∩B=∅} Show that cardS= 3^n |
Show that Σ_(k=0) ^n (C_n ^k )^2 =C_(2n) ^n |
In this covid −19 pandemic, it is known that are 5,667,355 confirmed cases out of 273,500,000 in X country population based WHO. One of the equipment to test the covid−19 is GeNose C19−S developed by UGM. GeNose C19−S is a rapid screening equipment for Sars−CoV2 virus infection through the breath of Covid −19 patient . It is claim that the sensivity of the test is 0,90 that is, if a person has the disease, then the probability that the diagnostic blood test comes back positive is 0,90. In addition , the specificity of the test is 0,95, i.e if a person is free the disease, then the probability that the diagnostic test comes back negative is 0,95. Let D and H is the event that a randomly selected individual has the disease and disease−free (healty), respectively. a. What is the positive predictive value of the GeNose C19−S test? That is, given that the blood test is positive for disease, what is the probability that person actually has the disease? b. If the doctor perfoms the test for the second time , taking P(D) equals to the value of probability you obtained from part a), determine the update positive predictive value of the test. |