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Concept drill

probability

GATE Civil Engineering · Probability and Geometry · 1998-2026

52
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85%
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0
elite explanations
21
years appeared

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B. S. Grewal — Higher Engineering Mathematics

Linear algebra, calculus, probability, numerical methods

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2026 Q26

Bag I contains 4 white and 6 black balls. Bag II contains 4 white and 3 black balls. One ball is drawn at random from any one of the two bags and it is found to be a black ball. Th...

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2026 Q32

The probability (in %) that a storm having return period of 15 years may occur in the next 10 years is ________ (rounded off to two decimal places).

mediumanswer key
2026 Q47

The age (in years) of a population is normally distributed with a mean of 36 and standard deviation of 12. The height (in cm) of the same population is also normally distributed wi...

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2025 Q14

X is a random variable that can take any one of the values 0, 1, 7, 11, and 12. The probability mass function for X is P(X = 0) = 0.4; P(X = 1) = 0.3; P(X = 7) = 0.1; P(X = 11) = 0...

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2025 Q22

Given that A and B are not null sets, which of the following statements regarding probability is/are CORRECT?

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2025 Q51

Consider a discrete random variable X whose probabilities are given below. The standard deviation of the random variable is ________ (round off to one decimal place). xi | 1 | 2 |...

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2025 Q63

A one-way, single lane road has traffic that consists of 30% trucks and 70% cars. The speed of trucks (in km/h) is a uniform random variable on the interval (30, 60), and the speed...

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2025 PYQ

Given that $A$ and $B$ are not null sets, which of the following statements regarding probability is/are CORRECT?

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2024 Q7

Three distinct sets of indistinguishable twins are to be seated at a circular table that has 8 identical chairs. Unique seating arrangements are defined by the relative positions o...

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2024 Q13

The probability that a student passes only in Mathematics is $\frac{1}{3}$. The probability that the student passes only in English is $\frac{4}{9}$. The probability that the stude...

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2024 Q36

In a sample of 100 heart patients, each patient has 80% chance of having a heart attack without medicine X. It is clinically known that medicine X reduces the probability of having...

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2024 Q47

The return period of a large earthquake for a given region is 200 years. Assuming that earthquake occurrence follows Poisson's distribution, the probability that it will be exceede...

mediumanswer key
2024 PYQ

The probability that a student passes only in Mathematics is $\frac{1}{3}$. The probability that the student passes only in English is $\frac{4}{9}$. The probability that the stude...

easyanswer keybasic explanation
2024 PYQ

The return period of a large earthquake for a given region is 200 years. Assuming that earthquake occurrence follows Poisson’s distribution, the probability that it will be exceede...

mediumbasic explanation
2024 PYQ

In a sample of 100 heart patients, each patient has 80% chance of having a heart attack without medicine X. It is clinically known that medicine X reduces the probability of having...

easyanswer keybasic explanation
2023 Q4

There are 4 red, 5 green, and 6 blue balls inside a box. If N number of balls are picked simultaneously, what is the smallest value of N that guarantees there will be at least two...

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2023 Q13

A remote village has exactly 1000 vehicles with sequential registration numbers starting from 1000. Out of the total vehicles, 30% are without pollution clearance certificate. Furt...

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2023 Q29

The probabilities of occurrences of two independent events A and B are 0.5 and 0.8, respectively. What is the probability of occurrence of at least A or B (rounded off to one decim...

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2023 PYQ

The probabilities of occurrences of two independent events A and B are 0.5 and 0.8, respectively. What is the probability of occurrence of at least A or B (rounded off to one decim...

easybasic explanation
2023 PYQ

A remote village has exactly 1000 vehicles with sequential registration numbers starting from 1000. Out of the total vehicles, 30% are without pollution clearance certificate. Furt...

easyanswer keybasic explanation
2022 Q49

A pair of six-faced dice is rolled thrice. The probability that the sum of the outcomes in each roll equals 4 in exactly two of the three attempts is ____________. (round off to th...

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2022 Q63

At a traffic intersection, cars and buses arrive randomly according to independent Poisson processes at an average rate of 4 vehicles per hour and 2 vehicles per hour, respectively...

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2022 PYQ

At a traffic intersection, cars and buses arrive randomly according to independent Poisson processes at an average rate of 4 vehicles per hour and 2 vehicles per hour, respectively...

mediumbasic explanation
2022 PYQ

A pair of six-faced dice is rolled twice. The probability that the sum of the outcomes in each roll equals 4 in exactly two of the three attempts is _________ (round off to three d...

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2022 PYQ

A flood control structure having an expected life of n years is designed by considering a flood of return period T years. When T = n, and n $$\to$$ $$\infty$$, the structures hydro...

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2021 Q3

Two identical cube shaped dice each with faces numbered 1 to 6 are rolled simultaneously. The probability that an even number is rolled out on each dice is:

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2021 Q9

In the figure shown above, PQRS is a square. The shaded portion is formed by the intersection of sectors of circles with radius equal to the side of the square and centers at S and...

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2021 Q30

Contractor X is developing his bidding strategy against Contractor Y. The ratio of Y's bid price to X's cost for the 30 previous bids in which Contractor X has competed against Con...

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2021 Q37

Vehicular arrival at an isolated intersection follows the Poisson distribution. The mean vehicular arrival rate is 2 vehicle per minute. The probability (round off to two decimal p...

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2020 Q18

The probability that a 50 year flood may NOT occur at all during 25 years life of a project (round off to two decimal places), is _________.

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2019 Q23

The probability that the annual maximum flood discharge will exceed 25000 m³/s, at least once in next 5 years is found to be 0.25. The return period of this flood event (in years,...

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2019 Q26

The probability density function of a continuous random variable distributed uniformly between x and y (for y > x) is

easyanswer key
2018 Q4

A three-member committee has to be formed from a group of 9 people. How many such distinct committees can be formed?

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2018 Q19

Probability (up to one decimal place) of consecutively picking 3 red balls without replacement from a box containing 5 red balls and 1 white ball is _________

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2018 Q20

A two-faced fair coin has its faces designated as head (H) and tail (T). This coin is tossed three times in succession to record the following outcomes: H, H, H. If the coin is tos...

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2018 Q25

Vehicles arriving at an intersection from one of the approach roads follow the Poisson distribution. The mean rate of arrival is 900 vehicles per hour. If a gap is defined as the t...

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2017 PYQ

A two-faced fair coin has its faces designated as head $$(H)$$ and tail $$(T)$$. This coin is tossed three times in succession to record the following outcomes: $$H, H,H.$$ If the...

easy
2017 PYQ

The number of parameters in the univariate exponential and Gaussian distributions, respectively, are

easyanswer key
2016 PYQ

$$X$$ and $$Y$$ are two random independent events. It is known that $$P(X)=0.40$$ and $$\,P\left( {X \cup {Y^C}} \right) = 0.7.$$ Which one of the following is the value of $$P\lef...

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2015 PYQ

Four cards are randomly selected from a pack of $$52$$ cards. If the first two cards are kings, what is the probability that the third card is a king?

easyanswer key
2014 PYQ

An observer counts $$240$$veh/h at a specific highway location. Assume that the vehicle arrival at the location is Poisson distributed, the probability of having one vehicle arrivi...

easy
2014 PYQ

A traffic office imposes on an average $$5$$ number of penalties daily on traffic violators. Assume that the number of penalties on different days is independent and follows a Pois...

easy
2014 PYQ

A fair (unbiased) coin was tossed four times in succession and resulted in the following outcomes; (i) Head, (ii) Head, (III) Head, (iv) Head. The probability of obtaining a ''Tail...

easyanswer key
2013 PYQ

A 1-hour rainfall of 10 cm has a return period of 50 years. The probability that 1 hour of rainfall 10 cm or more will occur in each of two successive years is

easyanswer key
2012 PYQ

Is an experiment, positive and negative values are equally likely to occur. The probability of obtaining at most one negative value in five trials is

easyanswer key
2012 PYQ

The annual precipitation data of a city is normally distributed with mean and standard deviation as $$1000$$mm and $$200$$ mm, respectively. The probability that the annual precipi...

easyanswer key
2011 PYQ

There are two containers with one containing $$4$$ red and $$3$$ green balls and the other containing $$3$$ blue balls and $$4$$ green balls. One ball is drawn at random from each...

easyanswer key
2010 PYQ

Two coins are simultaneously tossed. The probability of two heads simultaneously appearing

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2009 PYQ

The standard normal probability function can be approximated as $$$F\left( {{X_N}} \right) = {1 \over {1 + \exp \left( { - 1.7255{X_N}{{\left| {{X_N}} \right|}^{0.12}}} \right)}}\,...

mediumanswer key
2004 PYQ

A hydraulic structure has four gates which operate independently. The probability of failure of each gate is $$0.2.$$ Given that gate $$1$$ has failed, the probability that both ga...

easyanswer key
2003 PYQ

A box contains $$10$$ screws, $$3$$ of which are defective. Two screws are drawn at random with replacement. The probability that none of the two screws is defective will be

easyanswer key
1998 PYQ

The return period for the annual maximum flood of a given magnitude is 8 years. The probability that this flood magnitude will be executed once during the next 5 years is

mediumanswer key