GkSeries.com

NCERT Solutions for class 11 Maths | Chapter 7 - Permutations and Combinations

(1) 4 members form a group out of total 8 members.

(i) In how many ways it is possible to make the group if two particular members must be included.

(ii) In how many ways it is possible to make the group if two particular members must not be included?

[A] 15 and 360
[B] 15 and 15
[C] 30 and 360
[D] 360 and 360
Answer: 15 and 15
(2) Without repetition, using digits 2, 3, 4, 5, 6, 8 and 0, how many numbers can be made which lie between 500 and 1000?
[A] 70
[B] 147
[C] 60
[D] 90
Answer: 90

DOWNLOAD CURRENT AFFAIRS PDF FROM APP

(3) A box contains 4 black, 3 red and 6 green marbles. 2 marbles are drawn from the box at random. What is the probability that both the marbles are of the same color?
[A] 12/74
[B] 24/78
[C] 13/78
[D] None of these
Answer: 24/78
(4) There are 8 routes from London to Delhi. And there are 6 routes from Delhi to Tokyo. In how many different ways can Raj travel from London to Tokyo via Delhi?
[A] 100
[B] 48
[C] 24
[D] 14
Answer: 48
(5) If Suraj doesn’t want three vowels together, then in how many, can he arrange letters of the word 'MARKER'?
[A] 500
[B] 720
[C] 240
[D] 360
Answer: 240
(6) There are 30 people in a party. If everyone is to shake hands with one another, how many hand shakes are possible?
[A] 180
[B] 256
[C] 386
[D] 435
Answer: 435
(7) Mayur travels from Mumbai to Jammu in 7 different ways. But he is allowed to return to Mumbai by any way except the one he used earlier. In how many ways can he complete his journey?
[A] 49
[B] 42
[C] 48
[D] 6
Answer: 42
(8) A locker in bank has 3 digit lock. Mahesh forgot his password and was trying all possible combinations. He took 6 seconds for each try. The problem was that each digit can be from 0 to 9. How much time will be needed to by Mahesh to try all the combinations?
[A] 90 minutes
[B] 120 minutes
[C] 60 minutes
[D] 100 minutes
Answer: 100 minutes
(9) On a railway line there are 20 stops. A ticket is needed to travel between any 2 stops. How many different tickets would the government need to prepare to cater to all possibilities?
[A] 760
[B] 190
[C] 380
[D] 72
Answer: 380
(10) In a room there are 2 green chairs, 3 yellow chairs and 4 blue chairs. In how many ways can Raj choose 3 chairs so that at least one yellow chair is included?
[A] 3
[B] 30
[C] 64
[D] 84
Answer: 64
(11) The number of words, with or without meaning, can be formed using all the letters of the word EQUATION at a time so that the vowels and consonants occur together are
[A] 144
[B] 1044
[C] 1404
[D] 1440
Answer: 1440
(12) A committee of 7 has to be formed from 9 boys and 4 girls. In how many ways can this be done when the committee consists of at least 3 girls
[A] 588
[B] 885
[C] 858
[D] None of these
Answer: 588
(13) Six boys and six girls sit along a line alternately in x ways and along a circle (again alternatively in y ways), then
[A] x = y
[B] y = 12x
[C] x = 10y
[D] x = 12y
Answer: x = 12y
(14) 4 boys and 4 girls sit alternately in a row and then alternately along a circle. The ratio of number of ways of sitting in a row to the number of ways of sitting along a circle is
[A] 8 : 1
[B] 4 : 1
[C] 2 : 1
[D] none of these
Answer: 8 : 1
(15) In an examination, a question paper consists of 12 questions divided into two parts i.e. Part I and Part II, containing 5 and 7 questions, respectively. A student is required to attempt 8 questions in all, selecting at least 3 from each part. The number of ways a student can select the questions is
[A] 120
[B] 240
[C] 340
[D] 420
Answer: 420
(16) There are 10 points in a plane in which 4 points are collinear. The number of distinct straight lines can be formed by using these points
[A] 40
[B] 39
[C] 41
[D] none of these
Answer: 40
(17) Four dice are rolled. The number of possible outcomes in which at least one dice show 2 is
[A] 1296
[B] 671
[C] 625
[D] 585
Answer: 671
(18) A student is to answer 10 out of 13 questions in an examination such that he must choose at least 4 from the first five questions. The number of choices available to him is
[A] 40
[B] 196
[C] 280
[D] 346
Answer: 196
(19) A five digit number divisible by 3 is to be formed using the numerals 0, 1, 2, 3, 4 and 5 without repetition. The total number of ways in which this can be done is
[A] 216
[B] 600
[C] 240
[D] 3125
Answer: 216
(20) The English alphabet has 5 vowels and 21 consonants. The number of words with two different vowels and 2 different consonants can be formed from the alphabet is
[A] 504
[B] 5040
[C] 50400
[D] None of these
Answer: 50400

Please share this page

Chapters

Click Here to Read more questions

Teacher Eligibility Test