The diagram below shows the contents of a jar from which you select marbles at random.
There are 4 red marbles, 7 blue marbles, and 5 green marbles.
(A). What is the probability of selecting a red marble, replacing it, and then selecting a blue marble?
(B). What is the probability of selecting a red marble, setting it aside, and then selecting a blue marble?
(C). Are the answers to part (A) and part (B) the same? why or why not?
a) prob(red) = 4/16 = 1/4
your are replacing the marble, so you are back to 16
prob(blue) = 7/16
so prob(red, then blue) = (1/4)(7/16) = 7/64 or appr .109
b) prob(red) = 1/4 , just as before
but you are not returning the marble, so there are only 15 left
prob(blue) = 7/15
prob(red, then blue) = (1/4)(7/15) = 7/60 = appr .117
c) leave it up to you ....
Broooo this is a overdue lesson for me I need help
for c (this is what im putting to make sure to change it a bit) no they are not the same but at the same time are we got different numbers when we added it all up but in order to do so we had to use the same numbers aka 1/4 and 7 but we use 16 and 15 for the bottom half of the 7 but due to that we got different numbers
why did that person start talking about thermometers?
4/16 x 7/16= 7/64
a. The probability of selecting a red marble, replacing it, and selecting a blue marble is 7/64.
4/16 x 7/15=7/60
b. The probability of selecting a red marble, setting it aside, and selecting a blue marble is 7/60
c. The answers to parts (a) and (b) are NOT the same because in part (a we replaced the red marble that we selected so the theoretical possibility is the same for a marble. But in part (b) we set aside the marble so it changes the possibility of selecting a red marble and then a blue marble because the total number of marbles change.
This is what I said which change it a bit.