math series grade 4

The arrangement is as shown in the figure, the boy X will have B 2 , B 3 as neighbours. The girl Y will have G 2 , G 3 as neighbours. The two boys B 2 , B 3 can be arranged in two ways. The two girls G 2 , G 3 can be arranged in two ways. Hence, the total number of arrangements = 2 x 2 = ..

Question: Find n if P(n,4) = 20P(n,2) Answer: ..

(i) Note that the entries in a given matrix need not be distinct. (ii) The entries in this matrix are function of x. A matrix having m rows and n columns is called as matrix of order mxn. Such a matrix has mn elements. In general, an mxn matrix is in the form Where a i j represents the ele..

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Matrices and Determinants..

Matrices and Determinants..

Permutations and Combinations..

4. Sum the following: i) 1.2 + 2.4 + 3.8 +.... to n ter..

. Proceeding in this way, we see that there are n(n-1)(n-2)(n-3)(n-4)....[r factors] different ways of filling r blank spaces with n letters. The r t h factor = n - (r -1) = n - r = 1. The number of r-permutations of n different things is n P r = P(n,r) = n(n-1) (n-2) (n-3)...(n - r +..