Q74.Let ¯X and M.D. be the mean and the mean deviation about ¯X of n observations xi, i = 1, 2,n. If each of the observations is increased by 5 , then the new mean and the mean deviation about the new mean, respectively, are : – (1) ¯X , M.D. (2) X + 5, M.D. – (3) ¯X , M.D. +5 (4) X + 5, M.D. +5 JEE Main 2014 (12 Apr Online) JEE Main Previous Year Paper
What This Question Tests
This question tests the understanding of logical equivalences, specifically rewriting a conditional statement using disjunction and conjunction, which can be verified using standard logical identities.
Concepts Tested
Formulas Used
p => q is logically equivalent to ~p v q
Distributive laws of logic
📚 NCERT Sections This Tests
14.1 — In An N-Type Silicon, Which Of The Following Statement Is True:
Physics Class 12 · Chapter 14
14.1 In an n-type silicon, which of the following statement is true: (a) Electrons are majority carriers and trivalent atoms are the dopants. (b) Electrons are minority carriers and pentavalent atoms are the dopants. (c) Holes are minority carriers and pentavalent atoms are the dopants. (d) Holes are majority carriers and trivalent atoms are the dopants.
12.5 — A Hydrogen Atom Initially In The Ground Level Absorbs A Photon,
Physics Class 12 · Chapter 12
12.5 A hydrogen atom initially in the ground level absorbs a photon, which excites it to the n = 4 level. Determine the wavelength and frequency of photon.
14.2 — Which Of The Statements Given In Exercise 14.1 Is True For P-Type
Physics Class 12 · Chapter 14
14.2 Which of the statements given in Exercise 14.1 is true for p-type semiconductos.
📋 Question Details
- Chapter
- Mathematical Reasoning
- Topic
- Logical equivalence of statements
- Year
- 2014
- Shift
- 12 Apr Online
- Q Number
- Q74
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 14: Mathematical Reasoning
More from this Chapter
Q82.Let p be the statement " x is an irrational number", q be the statement " y is a transcendental number", and r be the statement " x is a rational number iff y is a transcendental number". Statement −1 : r is equivalent to either q or p Statement −2 : r is equivalent to ∼(p ↔∼q). (1) Statement −1 is false, Statement −2 is true (2) Statement −1 is true, Statement −2 is true, Statement −2 is a correct explanation for Statement −1 (3) Statement −1 is true, Statement −2 is true; (4) Statement −1 is true, Statement −2 is false. Statement −2 is not a correct explanation for Statement −1.
Q83.The statement p →(q →p) is equivalent to (1) p →(p →q) (2) p →(p ∨q) (3) p →(p ∧q) (4) p →(p ↔q)
Q70.Statement-1: ∼(p ↔∼q) is equivalent to p ↔q . Statement-2 : ∼(p ↔∼q) is a tautology. (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
Q73.Let S be a non-empty subset of R. Consider the following statement: P : There is a rational number x ∈S such that x > 0. Which of the following statements is the negation of the statement P ? JEE Main 2010 JEE Main Previous Year Paper (1) There is no rational number x ∈S such that (2) Every rational number x ∈S satisfies x ≤0 x ≤0 (3) x ∈S and x ≤0 ⇒x is not rational (4) There is a rational number x ∈S such that x ≤0