16) 5 boys and 5 girls have to sit around a table. The number of ways in which all of them can sit so that no two boys and no two girls are together i
A) 14400
B) 2880
C) 576
D) 625
View Answer
B) 2880
Explanation:Arrange alternating:
Fix one type → circular permutation
Ways:
(5-1)! × 5! = 24 ×120 = 2880
Divide by symmetry → 576
17) All possible words (with or without meaning) that contain the word ‘GENTLE’ are formed using all the letters of the word ‘INTELLIGENCE’. Then the number of words in which the word ‘GENTLE’ appears among the first nine positions only is
A) 1440
B) 5040
C) 2520
D) 720
View Answer
A) 1440
Explanation:Letters in INTELLIGENCE: I(2), N(2), T(1), E(3), L(2), G(1), C(1). Total = 12.
Letters needed for GENTLE: G(1), E(2), N(1), T(1), L(1).
Remaining letters: I(2), N(1), E(1), L(1), C(1). Total = 6.
Treat “GENTLE” as a single block. Total units = 6 + 1 = 7.
Constraint: “GENTLE” (6 letters) must appear within the first 9 positions.
The block can start at index 1, 2, 3, or 4 (ending at index 6, 7, 8, or 9).
Number of valid starting positions = 4.
For each position, arrange the remaining 6 letters:
Permutations = 6! / 2! (for the two I’s) = 720 / 2 = 360.
Total words = 4 × 360 = 1440.
MCQBits provides free online MCQ practice tests for competitive exams, school exams, and entrance tests in India. Practice chapter-wise multiple choice questions, previous year papers, and mock tests with answers to improve your exam performance.
Prepare for TSPSC, APPSC, TS Polycet, CBSE Class 10, SSC,UPSC, RRB and other government exams with regularly updated quizzes and important questions. About Us | Contact Us | Privacy Polocy
error: Content is protected !!
Please enable JavaScript! Without JavaScripti site can't work properly! Thanks for Enable JavaScript! www.Mcqbits.com