Kanchan has 10 friends among whom two are married to each other. She wishes to invite five of them for a party. If the married couples refuse to attend separately, then the number of different ways in she can invite five friends is a. `^8C_5` b. `2xx^8C_3` c. `^10 C_5-2xx^8C_4` d. none of these

A woman has 11 close friends.Number of ways in which she can invite 5 of them to dinner if two particular friends of them are not on speaking terms and will not attend together is

A man has 7 friends and he wants to invite 3 of them at a party. Find how many parties to each of 3 different friends he can give and how many times any particular friend will attend the parties?

A five-digit number is written down at random. The probability that the number is divisible by 5 and no two consecutive digits are Identical is a. 1/5 b. 1/5(9/(10))^3 c. (3/5)^4 d. none of these

Eight chairs are numbered 1 to 8. Two women and three men wish to occupy one chair each. First, the women choose the chairs from amongst the chairs marked 1 to 4, and then the men select th chairs from amongst the remaining. The number of possible arrangements is a.^6C_3xx^4C_2 b. ^4P_2xx^4P_3 c. ^4C_2xx^4P_3 d. none of these

If one numbers 80% of the other and 4 xx the sum of their squares is 656, then the numbers are 4,5 b.8,10 c.16,20 d.None of these

Two numbers are such that the square of one is 224 less than 8 times the square of the other. If the numbers be in the ratio of 3:4 the numbers are a. 6,8 b. 9,12 c. 12,16 d. none of these

The ages of five friends a, b, c, d, e with the age difference of 2 years each add upto 60. What is the age of c?

The number of ways in which a host lady can invite for a party of 8 out of 12 people of whom two do not want attend the party together is 2xx ^(11)C_7+ ^(10)C_8 b. ^(10)C_8+ ^(11)C_7 c. ^(12)C_8+ ^(10)C_6 d. none of these

Ramesh has 6 friends.In how many ways can be invite one or more of them at a dinner? (A) 61(B)62(C)63(D)64

Among the 8! [permutations of the digits 1, 2, 3..., 8, consider those arrangements which have the following property. If we take any five consecutive positions the product of the digits in these positions is divisible by 5. The number of such arrangements is equal to a. 7! b. 2.(7!) c. ^7C_4 d. none of these