two step equations math

Question: Prove that the number of ways in which (m+n) dissimilar things can be divided into two groups containing m and n Answer: If we select m things out of (m+n) things, then n things are left out . Then, this gives (m+n) that can be divided into two groups con..

i) Here, the total number = 6 + 6 = 12. 12 persons can be arranged in circular permutation as (12 - 1)! = 11! ways. ii) When 6 gentlemen are arranged around a table, there are 6 positions, each being between two gentlemen for 6 ladies, when no two ladies sit side by side. Now, ..

1. If a, x, b are in A.P, then x is called the arithmetic mean (A.M.) between the extremes a and b. 2. a. To insert n arithmetic means between two given quantities. Let a and b be any two given quantities, and let A 1 ,A 2 ,A 3 ,-----A n be n arithmetic means..

= (14 - 12) - (7 - 3) + (4 - 2) = 2 - 4 + 2 = 0 The system may have infinite number of solutions or no solution. Put x = k in (1) and (2) and solve y + z = 6 - k 2y + 3z = 14 - k. Solving the above two equations, we have z..

Number of ways of filling hundred's place = 2 Number of ways of filling ten's place = 2 Number of ways of filling unit's place = 2 By the fundamental principle of counting, the total number of numbers = 2 x 2 x 2 =..

Question: How many six digits telephone numbers can be made if each number starts with 45 and no digit appears more than once? Answer: The first two places are reserved for 4 and 5. The remaining 8 digits can be arranged in P(8,4) = 8.7.6.5 = 1680 way..

Question: A committee of 6 is chosen from 10 men and 7 women so as to contain atleast 3 men and 2 women. In how many different ways can this be done, if two particular women refuse to serve on the same committee? Answer: Let the two ladies who refuse to w..

Question: A candidate is required to answer 6 out of 10 questions, which are divided into two groups, each containing 5 questions, and he is not permitted to attempt more than 4 from each group. In how many ways can he make his choice? Answer: ..

Using matrix method solve the following systems of linear equations 2x - y + z = -3 3x - z = - 8 2x + 6y = 2..

Question: Find the number of diagonals in a polygon of n sides. Answer: In a polygon, no three points are collinear. To draw a line, we require two distinct points. The polygon of n sides has n distinct points. Number of diagonals that can be drawn ..