there are 18 girl and 12 boys on student council. If two student council member are selected at random, what is the probability that the first member is a boy and the second member is a boy?

The probability for the first member is a boy is the number of boys divided by the total number of students.

Now that you got that, there is one boy less and the total number of students are reduced by one.

To get the probability that the second member is a boy, divide the number of boys left by the number of students left.

Post your answers :)

first put your ration into lowest terms example 18:12= 3:2 go from there

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Originally Posted by starfirefly

first put your ration into lowest terms example 18:12= 3:2 go from there

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No, I'm sorry to disagree, but it's not like that.

The probability to have the first boy chosen is 12/30.

The probability of having the second boy chosen is 11/29 (since there is one boy less and one student from the total less)

Now, for both situations to occur together, you multiply the two probabilities, giving 66/435

Another way to look at it is with combos.

.

Which agrees with Unknown, but reduced to simplest terms.

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Originally Posted by Unknown008

No, I'm sorry to disagree, but it's not like that.

The probability to have the first boy chosen is 12/30.

The probability of having the second boy chosen is 11/29 (since there is one boy less and one student from the total less)

Now, for both situations to occur together, you multiply the two probabilities, giving 66/435

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Yup, this makes sense

Never mind.