An Urn Contains 2 Red and 2 Green Marbles

question 22

Multiple Choice

An urn contains 2 red and 2 green marbles. We pick a marble, record its color, and replace it. We repeat this procedure a second and a third time. The probability distribution for the number of red marbles is given below.

For this distribution, the probability of exactly one red marble is given by:

• A)1/8.
• B)3/8.
• C)7/8.
• D)1/3.

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Definitions:

Negative Reinforcer

A stimulus whose removal or avoidance following a behavior increases the likelihood of that behavior being repeated in the future.

More Likely

Indicates a higher probability or chance of something occurring compared to other possibilities.

Counterconditioning

A behavior therapy procedure that uses classical conditioning to evoke new responses to stimuli that are triggering unwanted behaviors.

Conditioned Response

A learned response to a previously neutral stimulus that has become associated with an unconditioned stimulus.