Tree Diagrams 5Solutiona Pboth marbles red P1st marble red

Tree Diagrams - 5

a. P(both marbles red) = P(1st marble red) *P(2nd marble is red | 1st marble is red) = 0.5*0.5 = 0.25 = 1/4

P(both marbles green) = P(1st marble green) *P(2nd marble is green | 1st marble is green) = 0.5*0.5 = 0.25 = 1/4

b. P(exactly 1 red)

= P(1st marble red) *P(2nd marble is green | 1st marble is red) + P(1st marble green) *P(2nd marble is red | 1st marble is green)

= 0.5*0.5 +0.5*0.5 = 0.25 + 0.25 = 0.50 = 1/2