Two marbles are drawn in succession from a box containing 10 red, 30 white, 20 blue and 15 orange marbles, with replacement being made after each drawing. Then the probability, that first drawn marble is red and second drawn marble is white, is
(4) 475
Total marbles =10+30+20+15=75
∵ with replacement, the two draws are independent
P= 1075 3075= 215 25= 475
Answer: (4)
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