There are 12 beads in a bag, all identical in shape but different in colour (4 are yellow, 3 are red, and 5 are blue). What is the likelihood of me picking out a blue and a yellow bead (in any order, and without replacement)
((4/12)(5/11)) + ((5/12)(4/11)) =((1/3)(5/11)) + ((5/12)(4/11)) =((1/3)(5/11)) + ((5/3)(1/11)) =5/33 + 5/33 =10/33
HO