Question 329566
A couple of ways to do this

let R =event of picking a rotten orange,  G=the event of picking a good orange

1. You want RRGG but there are 4C2 ways to get to RR out of a sample of 4.
Each time you select without replacement the number available dwindles by one.
P(2 rotten out of 4) = 4C2RRGG = 6* 8/50*7/49*42*48*41/47 =0.105 


2. The ways to select 2 rotten = 8C2=28, ways to select 2 good ones 42C2=861
   The ways to select 4 oranges out of 50 = 50C4=230,300

P(2 rotten out of 4) = 8C2*42C2/50C4= 28*861/230300=0.105