Math Chapter Wise

EnglishJSSC PGT 2018

Q121.Which one of the following statements is true?

AFor two random variables X and Y, if Cov (X, Y) = 0 (covariance) then the two random variables are independent. BIf V(X) = 0 (variance) then ⇒ P (X = 0) = 1 CLet F be the distribution function of a random variable. Then limn→∞ F (x + 1/n) always exists. DIf P (X ≤ 100) = 1, then E (X) (expectation) always exists.

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EnglishJSSC PGT 2018

Q122.What is the probability that in a random arrangement of English alphabets, the word "MOTHER" will appear?

A(1/6)3 B(20!)/(26!) C(21!/(26!) D(22!)/(26!)

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EnglishJSSC PGT 2018

Q123.Let X and Y be two independent N (0, 1) random variables. Find Cov (X + 3Y, 5X – 2Y).

A1 B–1 C0 D11

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EnglishOAVS TGT 2017

Q124.Two cards are drawn from a pack of cards one after the other. Find the probability that the first card is king and the second card is queen. If the first card is not replaced

A4/663 B1/13 C1/169 D4/51

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EnglishOAVS TGT 2017

Q125.If A and B are mutually exclusive events with P(B) ≠1, then P () A/B =?

A() 1 P B B() P A P B C() 1 1– P B D() P A 1– P B

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EnglishOAVS TGT 2017

Q126.According to Chebyshev's Inequality, which of following is true?

A() 2 Pr X – k 1/ k µ ≤ σ = B() 2 Pr X – k 1/ k µ ≥ σ ≥ C() 2 Pr X – k 1/ k µ ≥ σ ≤ D() 2 Pr X – k 1/ k µ ≥ σ =

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EnglishOAVS TGT 2017

Q127.A cumulative frequency graph is a:

ABar graph BCurve CStraight line DParabola

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EnglishOAVS TGT 2017

Q128.Age Frequency 18 12 19 5 20 3 21 9 22 1 23 8 24 12 25 12 26 5 27 3 Total 71 For the given data set what is the mode?

A19, 26 are modes BNo mode C20, 27 are modes D18, 24, 25 are modes

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EnglishOAVS TGT 2017

Q129.Let x1, x2 be the means of two samples of size n1, n2, then the mean X of combined sample of size n1 + n2 is:

A() 1 1 2 2 1 2 n x n x X n n × = × B() 1 1 2 2 1 2 n x n x X n – n + = C1 1 2 2 X n x n x = × D() 1 1 2 2 1 2 n x n x X n n × = +

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EnglishOAVS TGT 2017

Q130.A box contains cards numbered from 1 to 17. If one card is drawn at random from the box, find the probability that it bears a prime number.

A7/17 B9/17 C2/17 D11/17

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EnglishOAVS TGT 2017

Q131.A bag contains 5 red balls, 8 white balls, 4 green balls and 7 black balls, if one ball is drawn at random, find the probability that it is black.

A7/24 B7/17 C8/24 D5/24

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EnglishOAVS TGT 2017

Q132.Let A & B be two events with P(A)=1/2, P(B) = 1/3 and ∩ P(A B) = 1/4, then P(A/B) = _____.

A3/8 B4/7 C7/12 D3/4

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EnglishOAVS TGT 2017

Q133.In a survey conducted on 250 persons it was found that 180 drink tea and 70 drink coffee and 50 take both tea and coffee. How many drink neither?

A200 B60 C50 D110

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EnglishKVS TGT 2017

Q134.The standard deviation of the first n natural numbers is–

An 1/2 Bn(n 1)/2 C2 n 1 12 D(2n 1)(n 1)/6

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EnglishKVS TGT 2017

Q135.The mean of 100 observations is 50 and their standard deviation is 5. The sum of squares of all observations is–

A50,000 B2,50,000 C2,52,500 D2,55,000

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EnglishKVS TGT 2017

Q136.The probability that at least one of the events A and B occurs is 0.6. If A and B occur simultaneously with probability 0.2, then P(A) + P(B) is–

A0.4 B0.8 C1.2 D1.6

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EnglishKVS TGT 2017

Q137.A single letter is selected at random from the word 'PROBABILITY'. The probability that it is a vowel is:

A1/3 B4/11 C2/11 D3/11

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EnglishKVS TGT 2017

Q138.The number of possible outcomes, when a coin is tossed 6 times is–

A36 B32 C12 D64

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English

Q139.Everybody in a room shakes hands with everybody else. The total number of handshakes is 66. The total number of persons in the room is–

A11 B12 C13 D14

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EnglishKVS TGT 2017

Q140.The total number of 9 digit numbers which have all different digits is–

A10! B9! C10 10 D9 9!/×

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