Monthly Archives: February 2015

Independence of 3 Events

Posted on February 28, 2015 by Sumant Sumant

We all know the case for independence of two events which is . Now the questions is what are the conditions necessary for three events to be independent. Is it ? or there is more to it. The answer is … Continue reading →

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Random Variables

Posted on February 26, 2015 by Sumant Sumant

Loosely speaking a random variable is a numerical quantity whose value is determined by the outcome of a probabilistic experiment. Random variables are functions, What is the mapping? From i.e from Sample Space to Real numbers Domain of the Random … Continue reading →

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Conditional Probability

Posted on February 26, 2015 by Sumant Sumant

A conservative design team, call it and an innovative design team, call it are asked to separately design a new product within a month. From past experience we know that: The probability that team is successful is The probability that … Continue reading →

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Independence for three events

Posted on February 26, 2015 by Sumant Sumant

We all know the case for independence of two events which is . Now the questions is what are the conditions necessary for three events to be independent. Is it ? or there is more to it. The answer is … Continue reading →

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Hypergeometric Probabilities

Posted on February 26, 2015 by Sumant Sumant

An box contains balls, out of which are red. We want to choose balls, such that of them are red. Experiment: Picking balls out of balls where there are balls of red color and rest different. Sample space: . Event: Picking … Continue reading →

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The prisoner’s dilemma

Posted on February 24, 2015 by Sumant Sumant

The release of two out of three prisoners has been announced but their identity is kept secret. One of the prisoner considers asking a friendly guard to tell him who is the prisoner other than himself that will be released, … Continue reading →

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Proving Multinomial Theorem

Posted on February 23, 2015 by Sumant Sumant

Well if you understand Binomial expression . It basically partitions a set in to two subsets with one set containing elements and other set containing elements. What if we want to partition a set in to sets with elements in … Continue reading →

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Finding the square root of big perfect square

Posted on February 22, 2015 by Sumant Sumant

Watch this video The idea is similar to the one for digit number. However when you look at square the last digit could be and so we need a test to decide. So we find the first digit and then … Continue reading →

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Finding the cube roots of big perfect cubes

Posted on February 22, 2015 by Sumant Sumant

I found this on youtube The idea is very simple

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Probability Network Reliability Serial-Parallel

Posted on February 21, 2015 by Sumant Sumant

You can also watch the solution here. Network reliability. An electrical system consists of identical components, each of which is operational with probability p, independent of other components. The components are connected in three subsystems, as shown in the figure. … Continue reading →

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