Question

Ten of 16 students in Nyack's class are girls. His teacher selected two

helpers by randomly drawing names. He drew a boy's name first and
then a girl's name. Nyack thinks that the probability of this happening
is . Is he correct? If not, explain his error. 7.SP.8, 7.SP.8a, 7.SP.8b
15

Answer 1

I can't understand this after "happening is" but let's do it unaided.

The number of ways to draw a boy first is 6.

Given that, the number of ways to draw a girl next is 10.

That's out of a total of 16 x 15 length two permutations of 16 things

`p = (6 * 10)/(16(15)) = 1/4`

Answer: 1/4