##### Can't solve this probability tree?

 Mathematics Tutor: None Selected Time limit: 1 Day

Oct 2nd, 2015

In the box 11 balls

3 red, 4 blue and 4 yellow

probability of drawing yellow ball on second picking

(4/11) x (4/11) = 16/121 .....on first and second drawing of yellow ball only

(3/11) x (4/10) = 6/55........drawing a red ball followed by yellow one ( without replacement)

(4/11) x(4/10) = 8/55..........first pick being a blue ball followed by a yellow ball

1. overall probability of that the second ball drawn is yellow

16/121 + 6/55 + 8/55=234/605

probability of picking red ball on second drawing

(3/11) x (2/10) = 3/55

(4/11) x (3/10) = 6/55

(4/11) x (3/11) =12/121.....................here we replaced because the first pick was yellow!

2. 3/55 + 6/55 + 12/121 =159/605.............

hope that helps you, feel free to top up any point you ain't getting!

Oct 2nd, 2015

Thank you!!!

Oct 2nd, 2015

Thank you!!!

Oct 2nd, 2015

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Oct 2nd, 2015
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Oct 2nd, 2015
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