Permutations an...

How many different nine-digit numbers can be formed from the digits of the number 223355888 by rearrangement of the digits so that the odd digits occupy even places

There are three girls in a class of 10 students. The number of different ways in which they can be seated in a row such that no two of the three girls are together is

Eight chairs are numbered 1 to 8. Two women and three wish to occupy one chair each. First the women choose the chairs from amongst the chairs marked 1 to 4 and then men select the chairs from amongst the remaining . The number of possible arrangements is

The sides AB, BC, CA of a triangle ABC have respectively 3,4 and 5 points lying on them. The number of triangles that can be constructed using these points as vertices is

In a certain test a_i students gave wrong answers to at least i questions where i = 1,2,3,....k. No student gave more than k wrong answers.The total numbers of wrong answers given is

Six \'X\' s have to be placed in the square of the figure such that each row contains at least one X. In how many different ways can this be done

A committee of 12 is to be formed from 9 women and 8 men in which at least 5 women have to be included in a committee. Then the number of committees in which the women are in majority and men are in majority are respectively

The number of ways in which the following prizes be given to a class of 20 boys , first and second Mathematics , first and second Physics, first Chemistry and first English is