What is the number of ways of choosing 4 cards from pack of 52 playing cards is :( 4 A two are red cards and two are black cards B cards are of same Colour?

How many 3-digit odd numbers can be formed from the digits 1,2,3,4,5,6 if:
(a) the digits can be repeated (b) the digits cannot be repeated?

Number of places [(x), (y) and (z)] for them = 3Repetition is allowed and the 3-digit numbers formed are oddNumber of ways in which box (x) can be filled = 3 (by 1, 3 or 5 as the numbers formed are to be odd)

               m = 3

               n = 6

              p = 6

                                   m = 3

                              n = 5

                             p = 4

                                  = m x n x p = 3 x 5 x 4 = 60.