Question

there is a box of 20 munchkins that contains 5 jelly, 7 plain and 8 chocolate. Your friend chooses one and eats it. The you choose one and eat it

a. draw a tree diagram to shall ALL the different possible ways the experiment above could occur. Be sure to label the probability of each event occurring along the branched
b. What is the probability you other will the pick the same type of munchkin?
c. What is the probability you both eat a different munchkin?

Answer 1

easy

Answer 2

you can both either eat jelly, plain or chocolate

Answer 3

for some notation

J= jelly
P=plain
C=chocolate

Answer 4

so we can get either (JJ) OR ( PP) OR (CC)

Answer 5

let P= probability function

so P(XX) means the probability of getting XX

Answer 6

P(JJ) = (5/20) x ( 4/19)
P(PP) = (7/20) x (6/19 ) --> hopefully you dont get confused with this notation, prob should have thought ahead.
P(CC) = (8/20) x (7/19)

Answer 7

so for part b , you just add up all the probabilities above

\\Answer = [ (5/20) x (4/19) ] + [ (7/20) x (6/19) ] + [ (8/20) x (7/19) ]

Answer 8

then you can figure out on a calculator , I dont want to

Answer 9

now for part c . Note: COMPLEMENTARY events.

If they dont eat the same type , then they must have eaten different ones!

so the probability ( eating different ) = 1 - probability ( eating the same )

so the answer to part c is ( 1- (answer of b ) )

Answer 10

answer to b = 59/190

answer to c= 1 - ( 59/190) = 131/190