Permutation and combination
1. Number of selections of atleast 10 articles from 19 different articles is.
A) 2^19 B) 2^18 C) 2^19 - 1 D) 2^18 - 1 E) None
solution for question 13
solution for question 15 please
solution for question 18 please
solution for question 20 please
solution for question 35 please
solution for question 37 please.
solution for question 38 please
solution for question 40 please
Could you please share the solutions for the both the questions?
There are 40 lines in a plane of which a set of 12 lines are concurrent at A, another set of
15 lines are concurrent at B and the set of remaining lines are parallel. What is the number
of points of intersection of these 40 lines, given that the three sets are disjoint?
(A) 611 (B) 531 (C) 533 (D) 638
There are 33 similar chocolates to be distributed among 7 children such that each child gets distinct and natural number of chocolates. In how many ways it is possible ?
Sir , can you share the solution to this problem? I am getting B part as my answer , but in the key the ans given is C
81 students appeared the examinations in physics, chemistry and biology. 46 students passed in physics, 47 students passed in chemistry, and 48 students passed in biology; 29 students passed in physics and chemistry, 27 students passed in chemistry and biology, and 13 students passed in physics and biology. The largest possible number that could have passed all the three examinations is:
Is there any shortcut to find the number of squares in a rectangular chessboard? (eg. Number of squares in 8X10 chessboard?)