For #40 draw the same tree as it was in the class.

Again the question asks for the same color given :

two possibility it could be all red or all white.  

Conditional probability:

P(R2/R1)  = P(R2 and R1) / P (R1)

P(W2/W1) = P(W2 and W1) / P(w1)

Same as in #38 this is a dependent event try to rewrite the above formula.

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With replacement

P( same color) = (2/7) (2/7) + (5/7) (5/7) = 29/49

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For B: without replacement

Same reasoning as above:

P(same color) = (2/7) (1/6) + (5/7)(4/6) = 11/21

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