by shivamtripathi22 | Apr 10, 2022 | Uncategorized
(Q). 8 people are to be selected for a work from a group of 20 people such that exactly one from Mr. & Mrs. A is selected, similarly one from Mr. & Mrs. B and Mr. & Mrs. C and Mr. & Mrs. D is selected for the work. How many ways this can be...
by shivamtripathi22 | Apr 10, 2022 | Uncategorized
(Q). A set S has n elements. what is the number of subsets of this set which contains odd number of elements?Solution:-Total number of subset of this set = 2ⁿout of these half is even & half contains odd elements.Hence required number = = 2ⁿ⁻¹ ...
by shivamtripathi22 | Apr 10, 2022 | Uncategorized
(Q). 7 relative of a man comprises 4 ladies and 3 gentlmen; his wife has also 7 relatives; 3 of them are ladies & 4 gentlemen. In how many ways can they invite a dinner party of 3 ladies and 3 gentlemen so that there are 3 of man’s relative and 3 of the...
by shivamtripathi22 | Apr 10, 2022 | Uncategorized
(Q). A student is allowed to select at most n books from a collection of (2n+1) books. If the total number of ways in which he can select at least one book is 63, then what is the value of n?Solution:-total number of ways to select at least 1 & at most n books out...
by shivamtripathi22 | Apr 10, 2022 | Uncategorized
(Q). In a school, roll no. of k students are given from 1 to k. Three students are selected from these k students such that their roll numbers are not consecutive. In how many ways selection can be made? Solution:- roll numbers are:- 1, 2, 3, 4, 5, 6, 7,...
