Abox contains 3 red chips and 2 green chips. chips are drawn randomly, one at a time without replacement, until all 3 of the reds are drawn or until both green chips are drawn. what is the probability that the 3 reds are drawn

The total number of chips is 5; 

Without replacement, on the first try, there is 3/5 probability of getting a red chip. 
The second chip's probability would be 2/4 and the third being 1/3 

(3/5)(2/4)(1/3)=6/20 

Therefore, the probability of drawing 3 reds first is 6/20.

Hope I helped :) 

6(2x + 5y)6 (2x) = 12x6 (5y) = 30y12x + 30y