Q68.Let sets š“ and šµ have 5 elements each. Let the mean of the elements in sets š“ and šµ be 5 and 8 respectively and the variance of the elements in sets š“ and šµ be 12 and 20 respectively. A new set š¶ of 10 elements is formed by subtracting 3 from each element of š“ and adding 2 to each element of šµ. Then the sum of the mean and variance of the elements of š¶ is (1) 40 (2) 32 (3) 38 (4) 36 JEE Main 2023 (11 Apr Shift 1) JEE Main Previous Year Paper
What This Question Tests
This question evaluates the understanding of how mean and variance change when elements of a set are shifted or scaled, requiring calculation of mean and variance for a new combined set.
Concepts Tested
Formulas Used
Mean(x+c) = Mean(x)+c
Variance(x+c) = Variance(x)
Variance(ax) = a²Variance(x)
š NCERT Sections This Tests
13.2 ā Obtain The Binding Energy Of The Nuclei 5626Fe And 20983 Bi In Units Of
Physics Class 12 Ā· Chapter 13
13.2 Obtain the binding energy of the nuclei 5626Fe and 20983 Bi in units of MeV from the following data: m ( 5626Fe ) = 55.934939 u m ( 20983 Bi ) = 208.980388 u
3.10 ā In A Reaction Between A And B, The Initial Rate Of Reaction (R0) Was Measured
Chemistry Class 11 Ā· Chapter 3
3.10 In a reaction between A and B, the initial rate of reaction (r0) was measured for different initial concentrations of A and B as given below: A/ mol Lā1 0.20 0.20 0.40 B/ mol Lā1 0.30 0.10 0.05 r0/mol Lā1sā1 5.07 Ć 10ā5 5.07 Ć 10ā5 1.43 Ć 10ā4 What is the order of the reaction with respect to A and B? 3.11 The following results have been obtained during the kinetic studies of the reaction: 2A + B Ā® C + D Experiment [A]/mol Lā1 [B]/mol Lā1 Initial rate of formation of D/mol Lā1 minā1 I 0.1 0.1 6.0 Ć 10ā3 II 0.3 0.2 7.2 Ć 10ā2 III 0.3 0.4 2.88 Ć 10ā1 IV 0.4 0.1 2.40 Ć 10ā2 Determine the rate law and the rate constant for the reaction. 3.12 The reaction between A and B is first order with respect to A and zero order with respect to B. Fill in the blanks in the following table: Experiment [A]/ mol Lā1 [B]/ mol Lā1 Initial rate/ mol Lā1 minā1 I 0.1 0.1 2.0 Ć 10ā2 II ā 0.2 4.0 Ć 10ā2 III 0.4 0.4 ā IV ā 0.2 2.0 Ć 10ā2 3.13 Calculate the half-life of a first order reaction from their rate constants given below: (i) 200 sā1 (ii) 2 minā1 (iii) 4 yearsā1 3.14 The half-life for radioactive decay of 14C is 5730 years. An archaeological artifact containing wood had only 80% of the 14C found in a living tree. Estimate the age of the sample. 3.15 The experimental data for decomposition of N2O5 [2N2O5 Ā® 4NO2 + O2] in gas phase at 318K are given below: t/s 0 400 800 1200 1600 2000 2400 2800 3200 102 Ć [N2O5]/ 1.63 1.36 1.14 0.93 0.78 0.64 0.53 0.43 0.35 mol Lā1 (i) Plot [N2O5] against t. (ii) Find the half-life period for the reaction. (iii) Draw a graph between log[N2O5] and t. (iv) What is the rate law ? Chemistry 86 Reprint 2025-26 (v) Calculate the rate constant. (vi) Calculate the half-life period from k and compare it with (ii).
13.5 ā The Q Value Of A Nuclear Reaction A + B Ā® C + D Is Defined By
Physics Class 12 Ā· Chapter 13
13.5 The Q value of a nuclear reaction A + b Ā® C + d is defined by Q = [ mA + mb ā mC ā md]c2 where the masses refer to the respective nuclei. Determine from the given data the Q-value of the following reactions and state whether the reactions are exothermic or endothermic. (i) 11 H+13 H ā12 H+12 H (ii) 126 C+126 C ā1020 Ne+ 24 He Atomic masses are given to be m ( 12 H ) = 2.014102 u m ( 13 H) = 3.016049 u m ( 126 C ) = 12.000000 u m ( 1020 Ne ) = 19.992439 u
š Question Details
- Chapter
- Statistics
- Topic
- Mean and variance of grouped data
- Year
- 2023
- Shift
- 11 Apr Shift 1
- Q Number
- Q68
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 15: Statistics
More from this Chapter
Q98.The average marks of boys in a class is 52 and that of girls is 42 . The average marks of boys and girls combined is 50 . The percentage of boys in the class is (1) 40 (2) 20 (3) 80 (4) 60
Q84.The mean of the numbers a, b, 8, 5, 10 is 6 and the variance is 6.80. Then which one of the following gives possible values of a and b ? (1) a = 0, b = 7 (2) a = 5, b = 2 (3) a = 1, b = 6 (4) a = 3, b = 4 JEE Main 2008 JEE Main Previous Year Paper
Q71.If the mean deviation of number 1, 1 + d, 1 + 2d, ⦠. , 1 + 100d from their mean is 255 , then the d is equal to (1) 10.0 (2) 20.0 (3) 10.1 (4) 20.2
Q72.Statement-1 : The variance of first n even natural numbers is n2ā14 Statement-2 : The sum of first n natural numbers is n(n+1) 2 and the sum of squares of first n natural numbers is n(n+1)(2n+1)6 (1) Statement-1 is true, Statement-2 is true; (2) Statement-1 is true, Statement-2 is true; Statement-2 is a correct explanation for Statement-2 is not a correct explanation for Statement-1 Statement-1 (3) Statement-1 is true, Statement-2 is false (4) Statement-1 is false, Statement-2 is true