Most Important Selected Qs for JEE AdvancedMathematicsProbability
The contents of 3 bags w.r.t green and red marbles is as given in the table shown. A child randomly selects one of the bags, and draws a marble from it and retains it array |c|c|c| Bag & G & R A & 3 & 1 B & 2 & 2 C & 1 & 3 array If the marble is green, the child draws the second marbles randomly from one of the two remaining bags. If the first marble drawn is red the child draws one more marble from the same bag. The
Correct answer
217
Step-by-step solution
Let E : second drawn marble is green. aligned P(E) & = 1 3 [ 1 4 1+ 3 4 1 2 ( 1 2 + 1 4 ) + 1 2 2 3 + 1 2 ( 3 4 + 1 4 ) + 3 4 1 3 + 1 4 1 2 ( 3 4 + 1 2 ) ] & = 1 3 [ 1 4 + 3 8 3 4 + 1 2 ( 2 3 + 1 2 )+ ( 3 4 1 3 + 1 8 5 4 ) ]= 1 3 [ 1 4 + 9 32 + 7 12 + 13 32 ] & = 1 3 [ 24+27+56+39 96 ]= 1 3 [ 146 96 ]= 1 3 [ 73 48 ]= 73 144 Ans. aligned