Respuesta :
Probability ( 1 blue marble and 3 green marbles) = ( Blue, green, green, green) + ( green, blue, green, green) + ( green, green, blue, green) + ( green, green, green, blue) = { (8/13) × (5/12) × (4/11) × (3/10) } + { (5/13) × (8/12) × (4/11) × (3/10) } + { (5/13) × (4/12) × (8/11) × (3/10) } + { (5/13) × (4/12) × (3/11) × (8/10) } = (4/143) + (4/143) + (4/143)+ (4/143) = 16/143
If the answer does not correspond to yours, do tell me. I'll try to correct mine
P (1 blue, 3 green) = [tex] \frac{C (8, 1)*C(5, 3)}{C(13, 4)} = \frac{80}{715}= \frac{16}{143} } [/tex]