help me please..... who knows how to do the probabiltity question q2..
q: a fairground game involves trying to hit a moving target with a gunshot. a round consists of up to 3 shots. ten points are scored if a player hits the target, but the round is over if the player misses. linda has a constant probability of 0.6 of hitting the target and shots are INDEPENDENT OF ONE ANOTHER. (WHAT DOES THIS MEAN, HOW CAN I SHOW IT ON A TREE DIAGRAM OR ISIT A VENN DIAGRAM??)
a) find the probability that linda scores 30 points in a round
The r.v X is the no. of points linda scores in a round.
b) find the probability distribution of X
c) find the mean n SD of X
A game consists of 2 rounds
d)find the probability that linda scores more points in round 2 than in round 1.
Don't have the answers in front of me, but I sort of remember doing it a while back:
a) P(HHH) = 0.6 x 0.6 x 0.6
b) x 0 10 20 30
P(x)0.4 0.6x0.4 0.6x0.6x0.4 0.6x0.6x0.6
See the tree diagram attached. By independent- it just means that the probability of the next event happening is not dependent on the previous probability ie- a hit is always 0.6 and a miss is always 0.4.
c) Just use the formulas
d) Always write out what the possibilities are, so if she needs more points in round 2 than in round 1 you can write it out as:
Round 2 Round 1
P(10) P(0) Multiply each set together and add up all the probabilities and that's your answer