Afish tank in a pet store has 22 fish in it. 7 are orange and 15 are white. determine the probability that if we select 3 fish from the tank, at least 2 will be white.

Approximately 77.2%.

Step-by-step explanation:

At least two out of three fish are white means that

How many ways to choose two out of fifteen objects (white fish in this case?)

The combination formula gives the number of unique ways to choose out of objects. Note that in case of combination (as opposed to permutation,) the order of the objects does not matter.

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How many ways to choose one out of seven objects (orange fish in this case?)

Similarly, by the combination formula

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How many ways to choose two out of fifteen white fish and one out of seven orange fish at the same time? Since both events happen at the same time, the result is the product of the two numbers of ways:

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Similarly, the number of ways of choosing three out of fifteen white fish will be:

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It is not possible to choose both two and three white fish at the same time. In other words, one of the two situations may occur. Add the two numbers of ways to choose in each situation to find the total number of ways of choosing that satisfy the conditions.

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How many possible ways to choose three objects out of twenty-two in total (including ones that do not satisfy the condition?)

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The probability of meeting the requirements will be equal to

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auto insurance

step-by-step explanation:

21

step-by-step explanation: