Probability and Statistics · Engineering Mathematics · GATE IN

The probability that a thermistor randomly picked up from a production unit is defective is $$0.1.$$ The probability that out of $$10$$ thermistors randomly picked up, $$3$$ are defective is

A continuous random variable $$X$$ has a probability density function $$f\left( x \right) = {e^{ - x}},0 < x < \infty .$$ Then $$P\left\{ {X > 1} \right\}$$ is

Two independent random variables $$X$$ and $$Y$$ are uniformly distributed in the interval $$\left[ { - 1,1} \right].$$ The probability that max $$\left[ {X,Y} \right]$$ is less than $$1/2$$ is

A screening test is carried out to detect a certain disease. It is found that $$12$$% of the positive reports and $$15$$% of the negative reports are incorrect. Assuming that the probability of a person getting positive reports is $$0.01,$$ the probability that a person tested gets an incorrect reports is

A random variable is uniformly distributed over the interval $$2$$ to $$10.$$ Its variance will be

Assume that the duration in minutes of a telephone conversation follows the exponential distribution $$\,f\left( x \right) = {1 \over 5}{e^{ - x/5}},\,x \ge 0.\,\,\,$$ The probability that the conversation will exceed five minutes is

The probability that there are $$53$$ Sundays in a randomly chosen leap year is

The probability that a communication system will have high fidelity is $$0.81.$$ The probability that the system will have both high fidelity and high selectivity is $$0.18$$. The probability that a given system with high fidelity will have high selectivity is

An urn contains $$5$$ red and $$7$$ green balls. A ball is drawn at random and its colour is noted. The ball is placed back into the urn along with another ball of the same colour. The probability of getting a red ball in the next draw is

The probability density function of a random variable $$X$$ is $$\,{P_x}\left( x \right) = {e^{ - x}}\,\,$$ for $$\,\,x \ge 0\,\,$$ and $$0$$ otherwise. The expected value of the function $$\,{g_x}\left( x \right) = {e^{3x/4}}$$ is___________.

A coin is tossed thrice. Let $$X$$ be the event that head occurs in each of the first two tosses. Let $$Y$$ be the event that a tail occurs on the third toss. Let $$Z$$ be the event that two tails occur in three tosses. Based on the above information, which one of the following statements is TRUE?

Given that $$x$$ is a random variable in the range $$\left[ {0,\infty } \right]$$ with a probability density function $${{{e^{ - {x \over 2}}}} \over K},$$ the value of the constant $$K$$ is _______

The figure shown the schematic of a production process with machines $$A, B$$ and $$C.$$ An input job needs to be pre-processed either by $$A$$ or by $$B$$ before it is fed to $$C,$$ from which the final finished product comes out. The probabilities of failure of the machines are given as:
$${P_{\rm A}} = 0.15,\,\,{P_{\rm B}} = 0.05\,\,\& \,\,{P_C} = 0.1$$

Assuming independence of failures of the machines, the probability that a given job is successfully processed (up to the third decimal place) is _____.

A fair coin is tossed till a head appears for the first time. The probability that the number of required tosses is odd, is

The box $$1$$ contains chips numbered $$3, 6, 9,$$ $$12$$ and $$15$$. The box $$2$$ contains chips numbered $$6, 11, 16, 21$$ and $$26$$. Two chips, one from each box are drawn at random. The numbers written on these chips are multiplied. The probability for the product to be an even number is ______________.

Consider a Gaussian distributed random variable with zero mean and standard deviation $$\sigma .\,\,\,$$ The value of its cumulative distribution function at the origin will be

$${P_x}\left( X \right) = M{e^{\left( { - 2\left| x \right|} \right)}} + N{e^{\left( { - 3\left| x \right|} \right)}}\,\,$$ is the probability density function for the real random variable $$X,$$ over the entire $$x$$-axis, $$M$$ and $$N$$ are both positive real numbers. The equation relating $$M$$ and $$N$$ is