From the mathematical arrangement and combination, it can be calculated that because the two-color balls are not sorted, they are only combined, so if 33 red balls and 16 basketballs are selected, there are 1772 1088 possibilities.

There are 6 groups of red balls, one for each group 1-33, and 6 are not repeated. Then the blue ball is a two-color ball with a number drawn from 1- 16.

Two-color ball is a game of China Welfare Lottery. China welfare lottery "two-color ball" is a kind of "lottery-type" welfare lottery which is uniformly organized and distributed by China Welfare Lottery Distribution Management Center and sold nationwide. Since February 16, 2003, it has been sold on the national network. The computer network system is used for distribution and sales, and TV lottery is held regularly.