Question

If two different students are randomly selected from a class of 12 boys and 8 girls, what is the probability that both students are girls?

Answer 1

what are the answer choices?

Answer 2

There aren't any answer choices.

Answer 3

lel

Answer 4

Do you have any idea of what the answer is?

Answer 5

Well, the answer has to be in a common fraction if that helps.

Answer 6

number of wanted outcomes
------------------------
number of possible outcomes


i meant divide went i put ------

Answer 7

Thanks for the help!

Answer 8

the even of selects both students are girls = 8C2
and number possible outcomes = 20C2

so, P(G,G) = 8C2 / 20C2 = ...
just simplify the calculation above

Answer 9

use the combination formula
nCr = n!/(r!*(n-r)!)
so,
8C2 = 8!/(2!6!) = 8.7.6!/(2!6!) = 28 and
20C2 = 20!/(2!18!) = 20.9.18!/(2!18!) = 90

so, P(G,G) = 28/90 = 14/45

Answer 10

oppss.. i make a wrong, that should like this
8C2 = 8!/(2!6!) = 8.7.6!/(2!6!) = 28
20C2 = 20!/(2!18!) = 20.19.18!/(2!18!) = 190
so, P(G,G) = 28/190 = 14/95

Answer 11

that's 20 * 19 not 20 * 9