Question 1078362
P()=P(Pick a white ball)*P(Pick a white ball)*P(Pick a white ball)*P(Pick a white ball).

P(Pick a white ball)= 7/(6+7)=7/13.

P()=(7/13)^4 = 2401/28561 = 0.0841 = 8.41%

*******bonus: if the question switches to without replacement:

P() =P(pick a white ball)* P(pick another white ball) *P(pick another white ball(2)) * P(pick another white ball(3)).
P()= 7/(6+7) * 6/(6+6)* 5/(6+5)* 4/(6+4) = 7/143 = 0.0196 = 1.96%************* 

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