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Permutation and CombinationQuestion and Answers: Page 19 |
In how many ways can 4 boys and 3 girls stand in a straight line a. if there are no restrictions b. if the boys stand next to each other |
Find the probability that a student arranging the letters of the word MATHEMATICS will make all the vowels be together in any arrangement he or she does. |
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what will be the numbers of zeroes in the expension of a) 100!×25! b) 100!+25! please help |
How many numbers, divisible by 5, can be made with the digits 2,3,4 and 5 where no digit is being used more than once in each number? |
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Show that for n ∈ N, Σ_(r=0) ^n P_r ^n = ⌊n! e⌋ where ⌊x⌋ denotes the greatest integer ≤ x and P_r ^n = ((n!)/((n − r)!)) |
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Prove that 1. ((n),(r) ) = (((n−1)),(( r)) ) + (((n−1)),(( r−1)) ) 2. ((n),(r) ) + ((( n)),((r−1)) ) = (((n+1)),(( r)) ) 3. ((n),(0) )+ ((n),(1) )+ ((n),(2) )+..+ ((n),(n) )=2^n |
How many words with at least 2 letters can be formed using the letters from TINKUTARA? |
Such That a. _(n+1) C_r =(((n+1). _n C_r )/((n−r+1))) b. _n C_0 +_n C_2 +_n C_(4...) =_n C_1 +_n C_3 +_n C_(5...) =2^(n−1) |
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If all the words with or without meaning are written using the letters of the word QUEEN and are arranged as in English dictionary.What is the position of the word QUEEN? a)44th b)45th c)46th d)47th |
The sum of the digits in the unit place of all four digit numbers formed using the numbers 3 4 5 andL 6 without repetition is a)432 b)108 c)36 d)18 |
8 digit numbers are formed using 1 1 2 2 2 3 4 4. The number of such numbers in which the odd digits do not occupy odd places is a)160 b)120 c)60 d)48 |
An 8 digit number divisible by 9 is to be formed using digits from 0 to 9 without repeating the digits. The number of ways in which this can be done is? a)72(7i) b)18(7i) c)40(7i) d)36(7i) please I mean factorial by i.The part of my screen where the factorial symbol is isnt functioning.Thanks |
Q= In how many ways 8 students can be divided into two equal groups? Ans= ((8!)/(2!×(4!)^2 )) here why two factorial is divided? we do not do the same incase of distributing 52 cards equally among 4 persons. pls explain... |
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a man goes in for an examination in which there are 4 papers which maxmum of 10 marks for each paper the no of ways of getting 20 marks on the whole is ans:891 |
A delegation of 4 students is to be selected from a total of 12 students. In how many ways can the delegation be selected if: 1) 2 particular students wish to be included together only in the delegation? 2) 2 particular students refuse to be together and 2 other particular students wish to be together only in the delegation? |
5−digit number divisible by 3 formed using 0,1,2,3,4,5 without repetition. Total number of such no.s is ? |