Q18.Let the shortest distance from (a, 0), a > 0, to the parabola y2 = 4x be 4 . Then the equation of the circle passing through the point (a, 0) and the focus of the parabola, and having its centre on the axis of the parabola is : (1) x2 + y2 −10x + 9 = 0 (2) x2 + y2 −6x + 5 = 0 (3) x2 + y2 −4x + 3 = 0 (4) x2 + y2 −8x + 7 = 0
What This Question Tests
This question tests the ability to calculate total possible ways to choose two squares and then identify and count pairs of squares that do not share a side, finally computing the probability.
Concepts Tested
Formulas Used
nCr = n! / (r! * (n-r)!)
P(E) = (Favorable Outcomes) / (Total Outcomes)
📚 NCERT Sections This Tests
8.17 — Complete Each Synthesis By Giving Missing Starting Material, Reagent Or Products
Chemistry Class 12 · Chapter 8
8.17 Complete each synthesis by giving missing starting material, reagent or products
1.18 — A Point Charge Of 2.0 Mc Is At The Centre Of A Cubic Gaussian
Physics Class 11 · Chapter 1
1.18 A point charge of 2.0 mC is at the centre of a cubic Gaussian surface 9.0 cm on edge. What is the net electric flux through the surface?
10.2 — What Is The Shape Of The Wavefront In Each Of The Following Cases:
Physics Class 12 · Chapter 10
10.2 What is the shape of the wavefront in each of the following cases: (a) Light diverging from a point source. (b) Light emerging out of a convex lens when a point source is placed at its focus. (c) The portion of the wavefront of light from a distant star intercepted by the Earth.
📋 Question Details
- Chapter
- Permutation & Combination
- Topic
- Counting principles and probability
- Year
- 2025
- Shift
- 23 Jan Shift 2
- Q Number
- Q18
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 7: Permutations and Combinations
More from this Chapter
Q85.The set S = {1, 2, 3, … , 12) is to be partitioned into three sets A, B, C of equal size. Thus, A ∪B ∪C = S, A ∩B = B ∩C = A ∩C = ϕ . The number of ways to partition S is (1) 12! (2) 12! 3!(4!)3 3!(3!)4 (3) 12! (4) 12! (4!)3 (3!)4
Q74.In a shop there are five types of ice-creams available. A child buys six ice-creams. Statement -1: The number of different ways the child can buy the six ice-creams is 10C5 . Statement −2 : The number of different ways the child can buy the six ice-creams is equal to the number of different ways of arranging 6 A's and 4 B's in a row. (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.
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