Advertisements
Advertisements
प्रश्न
A man has 9 friends. 4 boys and 5 girls. In how many ways can he invite them if there have to be exactly 3 girls in the invitee's list?
विकल्प
320
160
80
200
Advertisements
उत्तर
160
Explanation:
Required number of ways
= `""^5C_3+""^5C_3 ""^4C_1+""^5C_3 ""^4C_2+""^5C_3 ""^4C_3+""^5C_3 ""^4C_4 `
= `""^5C_3(1+""^4C_1+""^4C_2+""^4C_3+""^4C_4)`
= `""^5C_3(1+4+6+4+1)`
= `(5!)/(3! 2!)xx16=160`
APPEARS IN
संबंधित प्रश्न
A group of 630 children is arranged in rows for a group photograph session. Each row contains three fewer children than the row in front of it. What number of rows is not possible?
Read the information given below and answer the question that follows.
Ten teams participated in a hockey tournament, in which every team played every other team once. After the tournament was over, it was found that the ten teams could be divided into 2 groups A and B, such that every team in A won against every team in B and every team in A won the same number of matches. If every team in A won 6 matches, how many teams were there in B?
Choose the most appropriate option.
In an office, 1/3 of the workers are Men, ½ of the men are married and 1/3 of the married men have children. If ¾ of the women are married and 2/3 of the married women have children, then the part of workers without children are:
x2(a-b) + a2(b-x) + b2(x-a) is factored as
How many numbers consisting of 5 digits can be formed in which the digits 3, 4 and 7 are used only once and digit 5 is used twice?
The number of ways of dividing 52 cards amongst four players, so that three players have 17 cards each and the fourth player has just one card, is.
In how many different ways can the letters of the word 'CORPORATION' be arranged, so that the vowels always come together?
In a group of 6 boys and 4 girls, four children are to be selected. In how many different ways can they be selected such that at least one boy should be there?
In how many ways a committee, consisting of 5 men and 6 women can be formed from 8 men and 10 women?
In how many ways can a group of 5 men and 2 women be made out of a total of 7 men and 3 women?
