-
question_answer1)
8 coins are tossed simultaneously. The probability of getting at least 6 heads is [AISSE 1985; MNR 1985; MP PET 1994]
A)
\[\frac{57}{64}\] done
clear
B)
\[\frac{229}{256}\] done
clear
C)
\[\frac{7}{64}\] done
clear
D)
\[\frac{37}{256}\] done
clear
View Solution play_arrow
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question_answer2)
In a box containing 100 eggs, 10 eggs are rotten. The probability that out of a sample of 5 eggs none is rotten if the sampling is with replacement is [MP PET 1991; MNR 1986; RPET 1995; UPSEAT 2000]
A)
\[{{\left( \frac{1}{10} \right)}^{5}}\] done
clear
B)
\[{{\left( \frac{1}{5} \right)}^{5}}\] done
clear
C)
\[{{\left( \frac{9}{5} \right)}^{5}}\] done
clear
D)
\[{{\left( \frac{9}{10} \right)}^{5}}\] done
clear
View Solution play_arrow
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question_answer3)
If the probability that a student is not a swimmer is 1/5, then the probability that out of 5 students one is swimmer is
A)
\[^{5}{{C}_{1}}{{\left( \frac{4}{5} \right)}^{4}}\left( \frac{1}{5} \right)\] done
clear
B)
\[^{5}{{C}_{1}}\,\frac{4}{5}\,{{\left( \frac{1}{5} \right)}^{4}}\] done
clear
C)
\[\frac{4}{5}{{\left( \frac{1}{5} \right)}^{4}}\] done
clear
D)
None of these done
clear
View Solution play_arrow
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question_answer4)
In a box of 10 electric bulbs, two are defective. Two bulbs are selected at random one after the other from the box. The first bulb after selection being put back in the box before making the second selection. The probability that both the bulbs are without defect is [MP PET 1987]
A)
\[\frac{9}{25}\] done
clear
B)
\[\frac{16}{25}\] done
clear
C)
\[\frac{4}{5}\] done
clear
D)
\[\frac{8}{25}\] done
clear
View Solution play_arrow
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question_answer5)
A fair coin is tossed n times. If the probability that head occurs 6 times is equal to the probability that head occurs 8 times, then n is equal to [Kurukshetra CEE 1998; AMU 2000]
A)
15 done
clear
B)
14 done
clear
C)
12 done
clear
D)
7 done
clear
View Solution play_arrow
-
question_answer6)
If three dice are thrown together, then the probability of getting 5 on at least one of them is
A)
\[\frac{125}{216}\] done
clear
B)
\[\frac{215}{216}\] done
clear
C)
\[\frac{1}{216}\] done
clear
D)
\[\frac{91}{216}\] done
clear
View Solution play_arrow
-
question_answer7)
If a dice is thrown 7 times, then the probability of obtaining 5 exactly 4 times is
A)
\[^{7}{{C}_{4}}\,{{\left( \frac{1}{6} \right)}^{4}}{{\left( \frac{5}{6} \right)}^{3}}\] done
clear
B)
\[^{7}{{C}_{4}}\,{{\left( \frac{1}{6} \right)}^{3}}{{\left( \frac{5}{6} \right)}^{4}}\] done
clear
C)
\[{{\left( \frac{1}{6} \right)}^{4}}{{\left( \frac{5}{6} \right)}^{3}}\] done
clear
D)
\[{{\left( \frac{1}{6} \right)}^{3}}{{\left( \frac{5}{6} \right)}^{4}}\] done
clear
View Solution play_arrow
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question_answer8)
If x denotes the number of sixes in four consecutive throws of a dice, then \[P\,(x=4)\]is [BIT Ranchi 1991]
A)
\[\frac{1}{1296}\] done
clear
B)
\[\frac{4}{6}\] done
clear
C)
1 done
clear
D)
\[\frac{1295}{1296}\] done
clear
View Solution play_arrow
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question_answer9)
A man make attempts to hit the target. The probability of hitting the target is \[\frac{3}{5}.\] Then the probability that A hit the target exactly 2 times in 5 attempts, is
A)
\[\frac{144}{625}\] done
clear
B)
\[\frac{72}{3125}\] done
clear
C)
\[\frac{216}{625}\] done
clear
D)
None of these done
clear
View Solution play_arrow
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question_answer10)
If a dice is thrown 5 times, then the probability of getting 6 exact three times, is
A)
\[\frac{125}{388}\] done
clear
B)
\[\frac{125}{3888}\] done
clear
C)
\[\frac{625}{23328}\] done
clear
D)
\[\frac{250}{2332}\] done
clear
View Solution play_arrow
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question_answer11)
The binomial distribution for which mean = 6 and variance = 2, is
A)
\[{{\left( \frac{2}{3}+\frac{1}{3} \right)}^{6}}\] done
clear
B)
\[{{\left( \frac{2}{3}+\frac{1}{3} \right)}^{9}}\] done
clear
C)
\[{{\left( \frac{1}{3}+\frac{2}{3} \right)}^{6}}\] done
clear
D)
\[{{\left( \frac{1}{3}+\frac{2}{3} \right)}^{9}}\] done
clear
View Solution play_arrow
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question_answer12)
A dice is thrown ten times. If getting even number is considered as a success, then the probability of four successes is
A)
\[^{10}{{C}_{4}}{{\left( \frac{1}{2} \right)}^{4}}\] done
clear
B)
\[^{10}{{C}_{4}}{{\left( \frac{1}{2} \right)}^{6}}\] done
clear
C)
\[^{10}{{C}_{4}}{{\left( \frac{1}{2} \right)}^{8}}\] done
clear
D)
\[^{10}{{C}_{6}}{{\left( \frac{1}{2} \right)}^{10}}\] done
clear
View Solution play_arrow
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question_answer13)
If the mean and variance of a binomial variate X are 2 and 1 respectively, then the probability that X takes a value greater than 1, is
A)
\[\frac{2}{3}\] done
clear
B)
\[\frac{4}{5}\] done
clear
C)
\[\frac{7}{8}\] done
clear
D)
\[\frac{15}{16}\] done
clear
View Solution play_arrow
-
question_answer14)
At least number of times a fair coin must be tossed so that the probability of getting at least one head is at least 0.8, is
A)
7 done
clear
B)
6 done
clear
C)
5 done
clear
D)
None of these done
clear
View Solution play_arrow
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question_answer15)
A biased coin with probability \[p,\,\,0<p<1,\]of heads is tossed until a head appears for the first time. If the probability that the number of tosses required is even is \[\frac{2}{5},\] then \[p=\]
A)
\[\frac{1}{2}\] done
clear
B)
\[\frac{1}{3}\] done
clear
C)
\[\frac{1}{4}\] done
clear
D)
None of these done
clear
View Solution play_arrow
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question_answer16)
The probability of a bomb hitting a bridge is \[\frac{1}{2}\]and two direct hits are needed to destroy it. The least number of bombs required so that the probability of the bridge beeing destroyed is greater then 0.9, is
A)
8 done
clear
B)
7 done
clear
C)
6 done
clear
D)
9 done
clear
View Solution play_arrow
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question_answer17)
If X follows a binomial distribution with parameters \[n=6\]and p. If \[9P\,(X=4)=P\,(X=2),\] then \[p=\]
A)
\[\frac{1}{3}\] done
clear
B)
\[\frac{1}{2}\] done
clear
C)
\[\frac{1}{4}\] done
clear
D)
1 done
clear
View Solution play_arrow
-
question_answer18)
A die is tossed thrice. If getting a four is considered a success, then the mean and variance of the probability distribution of the number of successes are [DSSE 1987]
A)
\[\frac{1}{2},\,\frac{1}{12}\] done
clear
B)
\[\frac{1}{6},\,\frac{5}{12}\] done
clear
C)
\[\frac{5}{6},\,\frac{1}{2}\] done
clear
D)
None of these done
clear
View Solution play_arrow
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question_answer19)
A die is tossed twice. Getting a number greater than 4 is considered a success. Then the variance of the probability distribution of the number of successes is [AISSE 1979]
A)
\[\frac{2}{9}\] done
clear
B)
\[\frac{4}{9}\] done
clear
C)
\[\frac{1}{3}\] done
clear
D)
None of these done
clear
View Solution play_arrow
-
question_answer20)
A die is thrown three times. Getting a 3 or a 6 is considered success. Then the probability of at least two successes is [DSSE 1981]
A)
\[\frac{2}{9}\] done
clear
B)
\[\frac{7}{27}\] done
clear
C)
\[\frac{1}{27}\] done
clear
D)
None of these done
clear
View Solution play_arrow
-
question_answer21)
In a simultaneous toss of four coins, what is the probability of getting exactly three heads [AI CBSE 1979]
A)
\[\frac{1}{2}\] done
clear
B)
\[\frac{1}{3}\] done
clear
C)
\[\frac{1}{4}\] done
clear
D)
None of these done
clear
View Solution play_arrow
-
question_answer22)
A coin is tossed successively three times. The probability of getting exactly one head or 2 heads, is [AISSE 1990]
A)
\[\frac{1}{4}\] done
clear
B)
\[\frac{1}{2}\] done
clear
C)
\[\frac{3}{4}\] done
clear
D)
None of these done
clear
View Solution play_arrow
-
question_answer23)
The items produced by a firm are supposed to contain 5% defective items. The probability that a sample of 8 items will contain less than 2 defective items, is [MP PET 1993]
A)
\[\frac{27}{20}\,{{\left( \frac{19}{20} \right)}^{7}}\] done
clear
B)
\[\frac{533}{400}\,{{\left( \frac{19}{20} \right)}^{6}}\] done
clear
C)
\[\frac{153}{20}\,{{\left( \frac{1}{20} \right)}^{7}}\] done
clear
D)
\[\frac{35}{16}\,{{\left( \frac{1}{20} \right)}^{6}}\] done
clear
View Solution play_arrow
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question_answer24)
The probability that a man can hit a target is \[\frac{3}{4}\]. He tries 5 times. The probability that he will hit the target at least three times is [MNR 1994]
A)
\[\frac{291}{364}\] done
clear
B)
\[\frac{371}{464}\] done
clear
C)
\[\frac{471}{502}\] done
clear
D)
\[\frac{459}{512}\] done
clear
View Solution play_arrow
-
question_answer25)
A fair coin is tossed a fixed number of times. If the probability of getting 7 heads is equal to that of getting 9 heads, then the probability of getting 3 heads is
A)
\[\frac{35}{{{2}^{12}}}\] done
clear
B)
\[\frac{35}{{{2}^{14}}}\] done
clear
C)
\[\frac{7}{{{2}^{12}}}\] done
clear
D)
None of these done
clear
View Solution play_arrow
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question_answer26)
A contest consists of predicting the results win, draw or defeat of 7 football matches. A sent his entry by predicting at random. The probability that his entry will contain exactly 4 correct predictions is
A)
\[\frac{8}{{{3}^{7}}}\] done
clear
B)
\[\frac{16}{{{3}^{7}}}\] done
clear
C)
\[\frac{280}{{{3}^{7}}}\] done
clear
D)
\[\frac{560}{{{3}^{7}}}\] done
clear
View Solution play_arrow
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question_answer27)
If there are n independent trials, p and q the probability of success and failure respectively, then probability of exactly r successes or Let p be the probability of happening an event and q its failure, then the total chance of r successes in n trials is [MP PET 1999]
A)
\[^{n}{{C}_{n+r}}{{p}^{r}}{{q}^{n-r}}\] done
clear
B)
\[^{n}{{C}_{r}}{{p}^{r-1}}{{q}^{r+1}}\] done
clear
C)
\[^{n}{{C}_{r}}{{q}^{n-r}}{{p}^{r}}\] done
clear
D)
\[^{n}{{C}_{r}}{{p}^{r+1}}{{q}^{r-1}}\] done
clear
View Solution play_arrow
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question_answer28)
A die is tossed thrice. A success is getting 1 or 6 on a toss. The mean and the variance of number of successes [AI CBSE 1985]
A)
\[\mu =1,\,\,{{\sigma }^{2}}=2/3\] done
clear
B)
\[\mu =2/3,\,\,{{\sigma }^{2}}=1\] done
clear
C)
\[\mu =2,\,\,{{\sigma }^{2}}=2/3\] done
clear
D)
None of these done
clear
View Solution play_arrow
-
question_answer29)
If X follows a binomial distribution with parameters \[n=6\]and \[p\]and \[4\,(P(X=4))=P(X=2),\] then \[p=\] [EAMCET 1994]
A)
\[\frac{1}{2}\] done
clear
B)
\[\frac{1}{4}\] done
clear
C)
\[\frac{1}{6}\] done
clear
D)
\[\frac{1}{3}\] done
clear
View Solution play_arrow
-
question_answer30)
The value of C for which \[P\,(X=k)=C{{k}^{2}}\]can serve as the probability function of a random variable X that takes 0, 1, 2, 3, 4 is [EAMCET 1994]
A)
\[\frac{1}{30}\] done
clear
B)
\[\frac{1}{10}\] done
clear
C)
\[\frac{1}{3}\] done
clear
D)
\[\frac{1}{15}\] done
clear
View Solution play_arrow
-
question_answer31)
In a bag there are three tickets numbered 1, 2, 3. A ticket is drawn at random and put back and this is done four times. The probability that the sum of the numbers is even, is
A)
\[\frac{41}{81}\] done
clear
B)
\[\frac{39}{81}\] done
clear
C)
\[\frac{40}{81}\] done
clear
D)
None of these done
clear
View Solution play_arrow
-
question_answer32)
In tossing 10 coins, the probability of getting exactly 5 heads is [MP PET 1996]
A)
\[\frac{9}{128}\] done
clear
B)
\[\frac{63}{256}\] done
clear
C)
\[\frac{1}{2}\] done
clear
D)
\[\frac{193}{256}\] done
clear
View Solution play_arrow
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question_answer33)
The probability that a bulb produced by a factory will fuse after 150 days of use is 0.05. What is the probability that out of 5 such bulbs none will fuse after 150 days of use
A)
\[1-{{\left( \frac{19}{20} \right)}^{5}}\] done
clear
B)
\[{{\left( \frac{19}{20} \right)}^{5}}\] done
clear
C)
\[{{\left( \frac{3}{4} \right)}^{5}}\] done
clear
D)
\[90\,{{\left( \frac{1}{4} \right)}^{5}}\] done
clear
View Solution play_arrow
-
question_answer34)
A dice is thrown 5 times, then the probability that an even number will come up exactly 3 times is
A)
\[\frac{5}{16}\] done
clear
B)
\[\frac{1}{2}\] done
clear
C)
\[\frac{3}{16}\] done
clear
D)
\[\frac{3}{2}\] done
clear
View Solution play_arrow
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question_answer35)
The records of a hospital show that 10% of the cases of a certain disease are fatal. If 6 patients are suffering from the disease, then the probability that only three will die is [MP PET 1998]
A)
\[1458\times {{10}^{-5}}\] done
clear
B)
\[1458\times {{10}^{-6}}\] done
clear
C)
\[41\times {{10}^{-6}}\] done
clear
D)
\[8748\times {{10}^{-5}}\] done
clear
View Solution play_arrow
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question_answer36)
Assuming that for a husband-wife couple the chances of their child being a boy or a girl are the same, the probability of their two children being a boy and a girl is [MP PET 1998]
A)
\[\frac{1}{4}\] done
clear
B)
1 done
clear
C)
\[\frac{1}{2}\] done
clear
D)
\[\frac{1}{8}\] done
clear
View Solution play_arrow
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question_answer37)
The probability that a student is not a swimmer is 1/5. What is the probability that out of 5 students, 4 are swimmers [DCE 1999]
A)
\[{}^{5}{{C}_{4}}{{\left( \frac{4}{5} \right)}^{4}}\frac{1}{5}\] done
clear
B)
\[{{\left( \frac{4}{5} \right)}^{4}}\frac{1}{5}\] done
clear
C)
\[{}^{5}{{C}_{1}}\frac{1}{5}{{\left( \frac{4}{5} \right)}^{4}}\times {}^{5}{{C}_{4}}\] done
clear
D)
None of these done
clear
View Solution play_arrow
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question_answer38)
An experiment succeeds twice as often as it fails. Find the probability that in 4 trials there will be at least three success [AMU 1999]
A)
\[\frac{4}{27}\] done
clear
B)
\[\frac{8}{27}\] done
clear
C)
\[\frac{16}{27}\] done
clear
D)
\[\frac{24}{27}\] done
clear
View Solution play_arrow
-
question_answer39)
The mean and variance of a binomial distribution are 6 and 4. The parameter n is [MP PET 2000]
A)
18 done
clear
B)
12 done
clear
C)
10 done
clear
D)
9 done
clear
View Solution play_arrow
-
question_answer40)
Five coins whose faces are marked 2, 3 are tossed. The chance of obtaining a total of 12 is [MP PET 2001; Pb. CET 2000]
A)
\[\frac{1}{32}\] done
clear
B)
\[\frac{1}{16}\] done
clear
C)
\[\frac{3}{16}\] done
clear
D)
\[\frac{5}{16}\] done
clear
View Solution play_arrow
-
question_answer41)
A bag contains 2 white and 4 black balls. A ball is drawn 5 times with replacement. The probability that at least 4 of the balls drawn are white is [AMU 2001]
A)
\[\frac{8}{141}\] done
clear
B)
\[\frac{10}{243}\] done
clear
C)
\[\frac{11}{243}\] done
clear
D)
\[\frac{8}{41}\] done
clear
View Solution play_arrow
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question_answer42)
A coin is tossed 2n times. The chance that the number of times one gets head is not equal to the number of times one gets tail is [DCE 2002]
A)
\[\frac{(2n!)}{{{(n!)}^{2}}}{{\left( \frac{1}{2} \right)}^{2n}}\] done
clear
B)
\[1-\frac{(2n!)}{{{(n!)}^{2}}}\] done
clear
C)
\[1-\frac{(2n!)}{{{(n!)}^{2}}}\,.\,\frac{1}{{{4}^{n}}}\] done
clear
D)
None of these done
clear
View Solution play_arrow
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question_answer43)
The mean and variance of a binomial distribution are 4 and 3 respectively, then the probability of getting exactly six successes in this distribution is [MP PET 2002]
A)
\[{}^{16}{{C}_{6}}{{\left( \frac{1}{4} \right)}^{10}}{{\left( \frac{3}{4} \right)}^{6}}\] done
clear
B)
\[{}^{16}{{C}_{6}}{{\left( \frac{1}{4} \right)}^{6}}{{\left( \frac{3}{4} \right)}^{10}}\] done
clear
C)
\[{}^{12}{{C}_{6}}{{\left( \frac{1}{4} \right)}^{10}}{{\left( \frac{3}{4} \right)}^{6}}\] done
clear
D)
\[^{12}{{C}_{6}}{{\left( \frac{1}{4} \right)}^{6}}{{\left( \frac{3}{4} \right)}^{6}}\] done
clear
View Solution play_arrow
-
question_answer44)
A die is tossed 5 times. Getting an odd number is considered a success. Then the variance of distribution of success is [AIEEE 2002]
A)
\[\frac{8}{3}\] done
clear
B)
\[\frac{3}{8}\] done
clear
C)
\[\frac{4}{5}\] done
clear
D)
\[\frac{5}{4}\] done
clear
View Solution play_arrow
-
question_answer45)
If two coins are tossed 5 times, then the probability of getting 5 heads and 5 tails is [AMU 2002]
A)
\[\frac{63}{256}\] done
clear
B)
\[\frac{1}{1024}\] done
clear
C)
\[\frac{2}{205}\] done
clear
D)
\[\frac{9}{64}\] done
clear
View Solution play_arrow
-
question_answer46)
In a binomial distribution the probability of getting a success is 1/4 and standard deviation is 3, then its mean is [EAMCET 2002]
A)
6 done
clear
B)
8 done
clear
C)
12 done
clear
D)
10 done
clear
View Solution play_arrow
-
question_answer47)
A coin is tossed 10 times. The probability of getting exactly six heads is [Kerala (Engg.) 2002]
A)
\[\frac{512}{513}\] done
clear
B)
\[\frac{105}{512}\] done
clear
C)
\[\frac{100}{153}\] done
clear
D)
\[{}^{10}{{C}_{6}}\] done
clear
View Solution play_arrow
-
question_answer48)
If a dice is thrown twice, the probability of occurrence of 4 at least once is [UPSEAT 2003]
A)
\[\frac{11}{36}\] done
clear
B)
\[\frac{7}{12}\] done
clear
C)
\[\frac{35}{36}\] done
clear
D)
None of these done
clear
View Solution play_arrow
-
question_answer49)
The mean and variance of a random variable X having a binomial distribution are 4 and 2 respectively, then \[P(X=1)\] is [AIEEE 2003]
A)
1/32 done
clear
B)
1/16 done
clear
C)
1/8 done
clear
D)
¼ done
clear
View Solution play_arrow
-
question_answer50)
A coin is tossed n times. The probability of getting head at least once is greater than 0.8, then the least value of n is [EAMCET 2003]
A)
2 done
clear
B)
3 done
clear
C)
4 done
clear
D)
5 done
clear
View Solution play_arrow
-
question_answer51)
A coin is tossed 3 times. The probability of getting exactly two heads is [SCRA 1980; MNR 1979]
A)
\[\frac{3}{8}\] done
clear
B)
\[\frac{1}{2}\] done
clear
C)
\[\frac{1}{4}\] done
clear
D)
None of these done
clear
View Solution play_arrow
-
question_answer52)
One coin is thrown 100 times. The probability of coming tail in odd number [MP PET 2004]
A)
\[\frac{1}{2}\] done
clear
B)
\[\frac{1}{8}\] done
clear
C)
\[\frac{3}{8}\] done
clear
D)
None of these done
clear
View Solution play_arrow
-
question_answer53)
A coin is tossed 3 times. The probability of obtaining at least two heads is or Three coins are tossed all together. The probability of getting at least two heads is [MP PET 1995]
A)
\[\frac{1}{8}\] done
clear
B)
\[\frac{3}{8}\] done
clear
C)
\[\frac{1}{2}\] done
clear
D)
\[\frac{2}{3}\] done
clear
View Solution play_arrow
-
question_answer54)
A dice is thrown two times. If getting the odd number is considered as success, then the probability of two successes is
A)
\[\frac{1}{2}\] done
clear
B)
\[\frac{3}{4}\] done
clear
C)
\[\frac{2}{3}\] done
clear
D)
\[\frac{1}{4}\] done
clear
View Solution play_arrow
-
question_answer55)
The mean and the variance of a binomial distribution are 4 and 2 respectively. Then the probability of 2 successes is [AIEEE 2004]
A)
\[\frac{28}{256}\] done
clear
B)
\[\frac{219}{256}\] done
clear
C)
\[\frac{128}{256}\] done
clear
D)
\[\frac{37}{256}\] done
clear
View Solution play_arrow
-
question_answer56)
If X has binomial distribution with mean np and variance npq, then \[\frac{P(X=k)}{P(X=k-1)}\] is [Pb. CET 2004]
A)
\[\frac{n-k}{k-1}.\frac{p}{q}\] done
clear
B)
\[\frac{n-k+1}{k}.\frac{p}{q}\] done
clear
C)
\[\frac{n+1}{k}.\frac{q}{p}\] done
clear
D)
\[\frac{n-1}{k+1}.\frac{q}{p}\] done
clear
View Solution play_arrow
-
question_answer57)
Two cards are drawn successively with replacement from a well shuffled deck of 52 cards then the mean of the number of aces is [J & K 2005]
A)
1/13 done
clear
B)
3/13 done
clear
C)
2/13 done
clear
D)
None of these done
clear
View Solution play_arrow
-
question_answer58)
A sample of 4 items is drawn at a random without replacement from a lot of 10 items. Containing 3 defective. If X denotes the number of defective items in the sample then \[P(0<x<3)\] is equal to [J & K 2005]
A)
\[\frac{3}{10}\] done
clear
B)
\[\frac{4}{5}\] done
clear
C)
\[\frac{1}{2}\] done
clear
D)
\[\frac{1}{6}\] done
clear
View Solution play_arrow