there are 12 students in a classroom, including the triplets joey, chloe, and zoe. If 3 of the 12 are randomly selcted to give speeches, what is the probability that joey with be first, chloe will be second, and zoe will be third?

A: 1/1320 B: 1/4 C: 1/48 D: 1/220

Respuesta :

AL2006

The probability of choosing Joey first is  1/12 .

If that happens, the probability of choosing Chloe next is  1/11 .

Then, the probability of choosing Zoe after that is  1/10 .

The probability of all these things happening is

          (1/12) x (1/11) x (1/10) 

       =  1/1320 = 0.00076 = 0.076 percent