Answer:

Step-by-step explanation:
The given ratio is 
9 is the common factor of 18 and 27
divide numerator and denominator by 9

hence
is proportion with 
Step-by-step explanation:
11/12-?=2/3
11/12-2/3=?
11-8/12=?
3/12
=1/4
The three whites:
(30 choose 1) * (29 choose 1) * (28 choose 1) = 30 * 29 * 28
The two reds:
(20 choose 1) * (19 choose 1) = 20 * 19
So, The three whites + two reds = 30 * 29 * 28 + 20 * 19 = 24740