At Westonci.ca, we make it easy to get the answers you need from a community of informed and experienced contributors. Get precise and detailed answers to your questions from a knowledgeable community of experts on our Q&A platform. Get immediate and reliable solutions to your questions from a community of experienced professionals on our platform.

A box has 1 red marble, 3 blue marbles, and 4 green marbles. Maya draws a blue marble randomly from the box, replaces it, and then draws another marble randomly. What is the probability of drawing 2 blue marbles in a row? Explain

Sagot :

Step-by-step explanation:

there are

1 red marble

3 blue marbles

4 green marbles

in the box.

that means there are 8 marbles in the box. which gives us 8 different outcomes for pulling randomly 1 marbles.

the probability for each of these 8 outcomes is equal : 1/8.

remember, the probability is always the number of desired cases over the number of total possible cases.

so, the probability of pulling a red marble is :

1 desired case

8 total cases

->

1/8 or 0.125

the probability of pulling a blue marble is :

3 desired cases

8 total cases

->

3/8 or 0.375

the probability of pulling a green marble is :

4 desired cases

8 total cases

->

4/8 = 1/2 or 0.5

now the experiment is pulling 2 marbles in a row, but the first pulled marble is put back into the box again.

this makes this a combined event, where the first AND the second event must fulfill the desired over total cases.

if the 2 events are independent (not overlapping or influencing each other), then we can simply multiply the probabilities. which is the case here, because the first marble is put back.

why ?

because now we have 8 possible outcomes for the first ball, and again 8 possible outcomes for the second ball, and when we combine all possibilities from the first with all possibilities from the second pull, we get 8×8 = 64 possible outcomes :

red. red

red. blue1

red. blue2

red. blue3

red. green1

...

green4 green4

so, the probability to pull a blue ball first is

3/8

and the probability to pull a blue ball second is

3/8 too

the combined probability of the combined event is

3/8 × 3/8 = 9/64

we have 3×3 = 9 desired outcomes of combining 3 blue and 3 blue balls out of the total of 64 possible outcomes.

Thanks for using our platform. We aim to provide accurate and up-to-date answers to all your queries. Come back soon. Thanks for stopping by. We strive to provide the best answers for all your questions. See you again soon. Keep exploring Westonci.ca for more insightful answers to your questions. We're here to help.