There is a bag with three black marbles, 5 yellow marbles, 2 white marbles, 4 blue marble, and 1 green marble what is the

**of picking a white or black marble?**

*probability*Any help is appreciated.

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There is a bag with three black marbles, 5 yellow marbles, 2 white marbles, 4 blue marble, and 1 green marble what is the

Any help is appreciated.

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Roughly: Probability of Event = (# of desired events)/(Total # of events)

Counting White or Black: 2 + 3

Counting All: 3+5+2+4+1

On the other hand, it's a TERRIBLE question!! The probability of an event must, of necessity, presuppose that one actually makes the attempt. If you NEVER draw a marble from the bag, the probability of drawing White or Black is zero (0).

Counting White or Black: 2 + 3

Counting All: 3+5+2+4+1

On the other hand, it's a TERRIBLE question!! The probability of an event must, of necessity, presuppose that one actually makes the attempt. If you NEVER draw a marble from the bag, the probability of drawing White or Black is zero (0).

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How many marbles are there - in total?

What is the probability of picking one white marble out of "all" those marbles? ........................................(1)

Similarly:

What is the probability of picking one black marble out of "all" those marbles? ........................................(2)

Add (1) and (2).....

It is a terrible question. The teacher presents it one way and then throws something different at the kids for their homework.Roughly: Probability of Event = (# of desired events)/(Total # of events)

Counting White or Black: 2 + 3

Counting All: 3+5+2+4+1

On the other hand, it's a TERRIBLE question!! The probability of an event must, of necessity, presuppose that one actually makes the attempt. If you NEVER draw a marble from the bag, the probability of drawing White of Black is zero (0).

The available answers are:

1/3 1/5 5/10 4/15. I think of the answers presented 1/3 makes the most sense. Right? But that would be picking both, not either or? I am so confused.

Thank you! So 1/5 is the answer if the available answers are 1/3, 1/5, 5/10 or 4/15.

How many marbles are there - in total?

What is the probability of picking one white marble out of "all" those marbles? ........................................(1)

Similarly:

What is the probability of picking one black marble out of "all" those marbles? ........................................(2)

Add (1) and (2).....

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Simply showing exact examples for every conceivable problem is not a good idea. If mathematics were all about memorizing, that might be fine. Part of the teaching of mathematics is the hope that a student might stretch and find solutions to problems they may not have seen, exactly.It is a terrible question. The teacher presents it one way and then throws something different at the kids for their homework.

The available answers are:

1/3 1/5 5/10 4/15. I think of the answers presented 1/3 makes the most sense. Right? But that would be picking both, not either or? I am so confused.

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How did you get 1/5?Thank you! So 1/5 is the answer if the available answers are 1/3, 1/5, 5/10 or 4/15.

Please note that "if the available answer are..." has very little to do with the correct solution to the problem. If the correct answer is not listed, the correct answer remains the correct answer.

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The problem with the question itself is that it is not worded very carefully. Something has to be said about how the choosing is done, like this: "one marble is chosen randomly", as opposed to "two marbles are chosen without replacement."It is a terrible question. The teacher presents it one way and then throws something different at the kids for their homework.

The available answers are:

1/3 1/5 5/10 4/15. I think of the answers presented 1/3 makes the most sense. Right?But that would be picking both, not either or?I am so confused.

The answer is 1/3; but your comment suggests you may have a common misunderstanding of the words "and" and "or" in probability. "Picking a white OR black marble" is satisfied (that is, the event occurs) when you pick

The same is true when we talk about sets. The set A = (1, 2} consists of the elements 1 AND 2, but would be described as "x is in the set if it is 1 OR 2". That's because in talking about sets or events, we are thinking of the

I meant 1/3 . 5/15 reduced to 1/3? Wrong???How did you get 1/5?

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We have all kinds, here. Ph.D.'s, professors, a few hacks, various sorts of teachers, website owners/administrators, scientists, and maybe an actuary. The same person may fall into multiple categories. We're all glad to help.Thank you so much. You have been so helpful. Are you a math teacher or educator?

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Count me in!… Others who wish to join the designation may do so voluntarily.

I gotta a bit of experience in a LOT of things, which means I'm accomplished in nothin'.