Hi, i have this question(adsbygoogle = window.adsbygoogle || []).push({});

A bag contains 5 red balls, 10 blue balls and 15 green balls. Three balls are drawn from the bag one after another without replacement. The eventR1,R2,B2andG3are defined as follows.

R1- represents the event the first ball drawn is red.

R2- represents the event the second ball drawn is red.

B2- represents the event the second ball drawn is blue.

G3- represents the event the third ball drawn is green.

Find

a) i) P(R1[tex]\cap[/tex]R2)

for this , i drew a tree diagram, for it to be red for the first ball, it has to be 5/30 and for the second to be red it has to be 4/29 thus multiplying them both would give me the answer which is 2/87.

ii) P(R1[tex]\cup[/tex]R2)

for this i thought of P(R1) + P (R2) - P(R1[tex]\cap[/tex]R2) would solve the problem but the answer is incorrect and later i see, i don't really know what's the probability ofR2because it could be 5/29 or 4/29.

Please help.

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# Homework Help: Probability question

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