Explore topic-wise MCQs in Joint Entrance Exam - Main (JEE Main).

This section includes 8666 Mcqs, each offering curated multiple-choice questions to sharpen your Joint Entrance Exam - Main (JEE Main) knowledge and support exam preparation. Choose a topic below to get started.

7701.

If the mean of the distribution is 2.6, then the value of y is Variate x 1 2 3 4 5 Frequency f of x 4 5 Y 1 2

A. 24
B. 13
C. 8
D. 3
Answer» D. 3
7702.

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

A. 50000
B. 250000
C. 252500
D. 255000
Answer» D. 255000
7703.

If a variable takes the discrete values \[\alpha -4,\,\alpha -\frac{7}{2},\,\alpha -\frac{5}{2},\,\alpha -3,\,\alpha -2,\,\alpha +\frac{1}{2},\,\alpha -\frac{1}{2},\,\alpha +5\,(\alpha >0)\], then the median is [DCE 1997; Pb. CET 1988]

A. \[\alpha -\frac{5}{4}\]
B. \[\alpha -\frac{1}{2}\]
C. \[\alpha -2\]
D. \[\alpha +\frac{5}{4}\]
Answer» B. \[\alpha -\frac{1}{2}\]
7704.

For a frequency distribution 7th decile is computed by the formula

A. \[{{D}_{7}}=l+\frac{\left( \frac{N}{7}-C \right)}{f}\times i\]
B. \[{{D}_{7}}=l+\frac{\left( \frac{N}{10}-C \right)}{f}\times i\]
C. \[{{D}_{7}}=l+\frac{\left( \frac{7N}{10}-C \right)}{f}\times i\]
D. \[{{D}_{7}}=l+\frac{\left( \frac{10N}{7}-C \right)}{f}\times i\]
Answer» D. \[{{D}_{7}}=l+\frac{\left( \frac{10N}{7}-C \right)}{f}\times i\]
7705.

The mode of the following items is 0, 1, 6, 7, 2, 3, 7, 6, 6, 2, 6, 0, 5, 6, 0 [AMU 1995]

A. 0
B. 5
C. 6
D. 2
Answer» D. 2
7706.

What is the standard deviation of the following series [DCE 1996] Measurements 0-10 10-20 20-30 30-40 Frequency 1 3 4 2

A. 81
B. 7.6
C. 9
D. 2.26
Answer» D. 2.26
7707.

Consider any set of observations \[{{x}_{1}},\,{{x}_{2}},\,.{{x}_{3}},.\,...,{{x}_{101}}\]; it being given that \[{{x}_{1}}

A. \[{{x}_{1}}\]
B. \[{{x}_{51}}\]
C. \[\frac{{{x}_{1}}+{{x}_{2}}+...+{{x}_{101}}}{101}\]
D. \[{{x}_{50}}\]
Answer» C. \[\frac{{{x}_{1}}+{{x}_{2}}+...+{{x}_{101}}}{101}\]
7708.

The quartile deviation for the following data is x : 2 3 4 5 6 f : 3 4 8 4 1 [AMU 1988; Kurukshetra CEE 1999]

A. 0
B. \[\frac{1}{4}\]
C. \[\frac{1}{2}\]
D. 1
Answer» E.
7709.

If the variance of observations \[{{x}_{1}},\,{{x}_{2}},\,......{{x}_{n}}\] is \[{{\sigma }^{2}}\], then the variance of \[a{{x}_{1}},\,a{{x}_{2}}.......,\,a{{x}_{n}}\], a ¹ 0 is

A. \[{{\sigma }^{2}}\]
B. \[a\,{{\sigma }^{2}}\]
C. \[{{a}^{2}}{{\sigma }^{2}}\]
D. \[\frac{{{\sigma }^{2}}}{{{a}^{2}}}\]
Answer» D. \[\frac{{{\sigma }^{2}}}{{{a}^{2}}}\]
7710.

If Q.D. is 16, the most likely value of S.D. will be

A. 24
B. 42
C. 10
D. None of these
Answer» B. 42
7711.

\[{{d}_{i}}\] is the deviation of a class mark \[{{y}_{i}}\] from ?a? the assumed mean and \[{{f}_{i}}\] is the frequency, if \[{{M}_{g}}=x+\frac{1}{\sum {{f}_{i}}}(\sum {{f}_{i}}{{d}_{i}})\], then x is

A. Lower limit
B. Assumed mean
C. Number of observations
D. Class size
Answer» C. Number of observations
7712.

If the mean of the set of numbers \[{{x}_{1}},\,{{x}_{2}},\,{{x}_{3}},\,.....,\,{{x}_{n}}\] is \[\bar{x}\], then the mean of the numbers \[{{x}_{i}}+2i\], \[1\le i\le n\] is [Pb. CET 1988]

A. \[\bar{x}+2n\]
B. \[\bar{x}+n+1\]
C. \[\bar{x}+2\]
D. \[\bar{x}+n\]
Answer» C. \[\bar{x}+2\]
7713.

If \[{{\bar{x}}_{1}}\] and \[{{\bar{x}}_{2}}\] are the means of two distributions such that \[{{\bar{x}}_{1}}

A. \[\bar{x}<{{\bar{x}}_{1}}\]
B. \[\bar{x}>{{\bar{x}}_{2}}\]
C. \[\bar{X}=\frac{{{{\bar{X}}}_{1}}+{{{\bar{X}}}_{2}}}{2}\]
D. \[{{\bar{x}}_{1}}<\bar{x}<{{\bar{x}}_{2}}\]
Answer» E.
7714.

The mean age of a combined group of men and women is 30 years. If the means of the age of men and women are respectively 32 and 27, then the percentage of women in the group is

A. 30
B. 40
C. 50
D. 60
Answer» C. 50
7715.

If the algebraic sum of deviations of 20 observations from 30 is 20, then the mean of observations is

A. 30
B. 30.1
C. 29
D. 31
Answer» E.
7716.

If two sets A and B are having 99 elements in common, then the number of elements common to each of the sets \[A\times B\] and \[B\times A\] are [Kerala (Engg.) 2004]

A. \[{{2}^{99}}\]
B. \[{{99}^{2}}\]
C. 100
D. 18
Answer» C. 100
7717.

If \[A=\{1,\,2,\,3,\,4\}\]; \[B=\{a,\,b\}\] and f is a mapping such that \[f:A\to B\], then \[A\times B\] is [DCE 2005]

A. {(a, 1), (3, b)}
B. {(a, 2), (4, b)}
C. {(1, a), (1, b), (2, a), (2, b), (3, a), (3, b), (4, a), (4, b)}
D. None of these
Answer» D. None of these
7718.

In a class of 30 pupils, 12 take needle work, 16 take physics and 18 take history. If all the 30 students take at least one subject and no one takes all three then the number of pupils taking 2 subjects is [J & K 2005]

A. 16
B. 6
C. 8
D. 20
Answer» B. 6
7719.

In a battle 70% of the combatants lost one eye, 80% an ear, 75% an arm, 85% a leg, x% lost all the four limbs. The minimum value of x is

A. 10
B. 12
C. 15
D. None of these
Answer» B. 12
7720.

The number of proper subsets of the set {1, 2, 3} is [JMIEE 2000]

A. 8
B. 7
C. 6
D. 5
Answer» D. 5
7721.

The shaded region in the given figure is [NDA 2000]

A. \[A\text{ }\cap \text{ }\left( B\text{ }\cup \text{ }C \right)\]
B. \[A\text{ }\cup \text{ }\left( B\text{ }\cap \text{ }C \right)\]
C. \[A\text{ }\cap \text{ }\left( B\text{ }-\text{ }C \right)\]
D. \[A\text{ }-\text{ }\left( B\text{ }\cup \text{ }C \right)\]
Answer» E.
7722.

If A and B are two sets, then \[A\cap (A\cup B{)}'\] is equal to

A. A
B. B
C. \[\varphi \]
D. None of these
Answer» D. None of these
7723.

If A, B, C be three sets such that \[A\text{ }\cup \text{ }B\text{ }=\text{ }A\text{ }\cup \text{ }C\] and\[A\text{ }\cap \text{ }B\text{ }=\text{ }A\text{ }\cap \text{ }C,\] then [Roorkee 1991]

A. A = B
B. B = C
C. A = C
D. A = B = C
Answer» C. A = C
7724.

If the set A has p elements, B has q elements, then the number of elements in A × B is [Karnataka CET 1999]

A. \[p+q\]
B. \[p+q+1\]
C. \[pq\]
D. \[{{p}^{2}}\]
Answer» D. \[{{p}^{2}}\]
7725.

If A, B and C are any three sets, then A - (B U C) is equal to

A. (A - B) U (A - C)
B. (A - B) U (A - C)
C. (A - B) U C
D. (A - B) U C
Answer» C. (A - B) U C
7726.

Let \[A=[x:x\in R,\,|x|\,

A. \[[x:1<x\le 2]\]
B. \[[x:1\le x<2]\]
C. \[[x:1\le x\le 2]\]
D. None of these
Answer» C. \[[x:1\le x\le 2]\]
7727.

Two finite sets have m and n elements, the total number of subsets of the first set is 56 more than the total number of subsets of the second set. Then:

A. \[m=3,n=6\]
B. \[m=6,n=3\]
C. \[m=5,n=6\]
D. None of these
Answer» C. \[m=5,n=6\]
7728.

Given \[n(U)=20,n(A)=12,n(B)=9,n(A\cap B)=4,\]where U is the universal set, A and B are subsets of U, then \[n({{(A\cup B)}^{c}})=\]

A. 17
B. 9
C. 11
D. 3
Answer» E.
7729.

If A and B are two disjoint sets, then which one of the following is correct?

A. \[A-B=A-(A\cap B)\]
B. \[B-A'=A\cap B\]
C. \[A\cap B=(A-B)\cap B\]
D. All of these
Answer» B. \[B-A'=A\cap B\]
7730.

If A, B and C are three finite sets, then what is \[\left[ (A\cup B)\cap C \right]'\] equal to?

A. \[A'\cup B'\cap C'\]
B. \[A'\cap B'\cap C'\]
C. \[A'\cap B'\cup C'\]
D. \[A\cap B\cap C\]
Answer» D. \[A\cap B\cap C\]
7731.

\[{{x}^{2}}=xy\] is a relation which is [Orissa JEE 2005]

A. Symmetric
B. Reflexive
C. Transitive
D. None of these
Answer» C. Transitive
7732.

The relation R is defined on the set of natural numbers as {(a, b) : a = 2b}. Then \[{{R}^{-1}}\] is given by

A. {(2, 1), (4, 2), (6, 3).....}
B. {(1, 2), (2, 4), (3, 6)....}
C. \[{{R}^{-1}}\] is not defined
D. None of these
Answer» C. \[{{R}^{-1}}\] is not defined
7733.

Let R be a relation over the set N × N and it is defined by \[(a,\,b)R(c,\,d)\Rightarrow a+d=b+c.\] Then R is

A. Reflexive only
B. Symmetric only
C. Transitive only
D. An equivalence relation
Answer» E.
7734.

R is a relation over the set of real numbers and it is given by \[nm\ge 0\]. Then R is

A. Symmetric and transitive
B. Reflexive and symmetric
C. A partial order relation
D. An equivalence relation
Answer» E.
7735.

The relation R defined on a set A is antisymmetric if \[(a,\,b)\in R\Rightarrow (b,\,a)\in R\] for

A. Every (a, b) \[\in R\]
B. No \[(a,\,b)\in R\]
C. No \[(a,\,b),\,a\ne b,\,\in R\]
D. None of these
Answer» D. None of these
7736.

An integer m is said to be related to another integer n if m is a multiple of n. Then the relation is

A. Reflexive and symmetric
B. Reflexive and transitive
C. Symmetric and transitive
D. Equivalence relation
Answer» C. Symmetric and transitive
7737.

Let A = {1, 2, 3}, B = {1, 3, 5}. If relation R from A to B is given by R ={(1, 3), (2, 5), (3, 3)}. Then \[{{R}^{-1}}\] is

A. {(3, 3), (3, 1), (5, 2)}
B. {(1, 3), (2, 5), (3, 3)}
C. {(1, 3), (5, 2)}
D. None of these
Answer» B. {(1, 3), (2, 5), (3, 3)}
7738.

Let \[X=\{1,\,2,\,3,\,4,\,5\}\] and \[Y=\{1,\,3,\,5,\,7,\,9\}\]. Which of the following is/are relations from X to Y

A. \[{{R}_{1}}=\{(x,\,y)|y=2+x,\,x\in X,\,y\in Y\}\]
B. \[{{R}_{2}}=\{(1,\,1),\,(2,\,1),\,(3,\,3),\,(4,\,3),\,(5,\,5)\}\]
C. \[{{R}_{3}}=\{(1,\,1),\,(1,\,3)(3,\,5),\,(3,\,7),\,(5,\,7)\}\]
D. \[{{R}_{4}}=\{(1,\,3),\,(2,\,5),\,(2,\,4),\,(7,\,9)\}\]
Answer» C. \[{{R}_{3}}=\{(1,\,1),\,(1,\,3)(3,\,5),\,(3,\,7),\,(5,\,7)\}\]
7739.

Let n = n. Then the number of all relations on A is

A. \[{{2}^{n}}\]
B. \[{{2}^{(n)!}}\]
C. \[{{2}^{{{n}^{2}}}}\]
D. None of these
Answer» D. None of these
7740.

If A={0},B={l, 2}, and C={3}, then\[A\times B\times C\]is

A. {(0, 1, 3), (0, 2, 3)}
B. {(0, 1, 2), (0, 2, 3)}
C. \[\phi \]
D. {(0, 2, 3), (1, 2, 3)}
Answer» B. {(0, 1, 2), (0, 2, 3)}
7741.

Number of solutions of the equation \[\left| 2-\left| x \right| \right|=x+4\] is _________.

A. 2
B. 4
C. 1
D. 5
Answer» D. 5
7742.

If A = {x|x \[\in \] N and x \[\le \] 5}, B = {2, 3, 6, 7} then \[(A-B)\cap (B-A)\]

A. {1, 4, 5, 6, 7}
B. {1, 4, 5}
C. {6, 7}
D. \[\phi \]
Answer» E.
7743.

If A=\[\{x|x\in \,N\,\]and \[({{x}^{2}}-4)\]\[({{x}^{2}}-5)\]=0} and B=\[\{x|x\in {{l}^{+}}\]and \[x(x-1)\]\[(x-2)\]=0} then \[(A\cup B)\]-\[(A\cap B)\]is

A. {1, 2}
B. {1}
C. {2}
D. \[\phi \]
Answer» C. {2}
7744.

The roots of the equation \[{{(x-1)}^{2}}-4\left| x-1 \right|+3=0\]

A. Form an A.P.
B. Form a G.P.
C. Form an H.P.
D. Do not form any progression
Answer» B. Form a G.P.
7745.

The least value of n (a natural number), for which the sum S of the series \[1+\frac{1}{2}+\frac{1}{{{2}^{2}}}+\frac{1}{{{2}^{3}}}+.....\]differs from \[{{S}_{n}}\] by a quantity \[

A. 21
B. 20
C. 19
D. None
Answer» B. 20
7746.

The sum of \[\frac{\frac{1}{2}.\frac{2}{2}}{{{1}^{3}}}+\frac{\frac{2}{2}.\frac{3}{2}}{{{1}^{3}}+{{2}^{3}}}+\frac{\frac{3}{2}.\frac{4}{2}}{{{1}^{3}}+{{2}^{3}}+{{3}^{3}}}+.....\] upto n terms is equal to

A. \[\frac{n-1}{n}\]
B. \[\frac{n}{n+1}\]
C. \[\frac{n+1}{n+2}\]
D. \[\frac{n+1}{n}\]
Answer» C. \[\frac{n+1}{n+2}\]
7747.

The 100th term of the sequence 1, 2, 2, 3, 3, 3, 4, 4, 4, 4,... is

A. 12
B. 13
C. 14
D. 15
Answer» D. 15
7748.

If the positive integers a, b, c, d are in AP, then the numbers abc, abd, acd, bcd are in

A. HP
B. AP
C. GP
D. None of the above
Answer» B. AP
7749.

If the nth term of an arithmetic progression is\[3n+7\], then what is the sum of its first 50 terms?

A. 3925
B. 4100
C. 4175
D. 8200
Answer» D. 8200
7750.

If a, b, c are positive numbers, then least value of\[(a+b+c)\left( \frac{1}{a}+\frac{1}{b}+\frac{1}{c} \right)\] is

A. 1
B. 6
C. 9
D. None
Answer» D. None