Suppose we have four boxes A,B,C and D containing coloured marbles as given below : One of the boxes has been selected at random and a single marble is drawn from it. If the marble is red, what is the probability that it was drawn from box A? bo

Explanation

R=choosing the red marble.


`E_{A^{prime}}`= selecting the box A



`E_{B^{prime}}`= selecting the box B



`E_{C}`= selecting the box C


Total marbles =`40`


red marbles =`15`

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