An urn contains 5 different red and 6 different green balls. In how many ways can 6 balls be selected so that there are at least two balls of each colour?
The correct option is A 425
Total number of red balls = 5
Total number of green balls = 6
Possbile combination are:
Required number of selections = (5C2×6C4) + (5C3×6C3) + (5C4×6C2) = 425