There are two types of Bingo cards. One is a 5x5 grid meant for
75-ball Bingo, which is largely played in the U.S. The other uses a 9x3 grid for
U.K. style "Housie" or 90-ball Bingo.
75-ball bingo cards Players use cards that feature five columns of five squares each, with every square containing a number (except the middle square, which is designated a "FREE" space). The columns are labeled "B" (numbers 1–15), "I" (numbers 16–30), "N" (numbers 31–45), "G" (numbers 46–60), and "O" (numbers 61–75).
Randomization A popular Bingo myth claims that U.S. Bingo innovator Edwin S. Lowe contracted Columbia University professor Carl Leffler to create 6,000 random and unique Bingo cards. The effort is purported to have driven Leffler insane. Manual
random permutation is an onerous and time-consuming task that limited the number of Bingo cards available for play for centuries. The calculation of random permutations is a matter of
statistics principally relying on the use of
factorial calculations. In its simplest sense, the number of unique "B" columns assumes that all 15 numbers are available for the first row. That only 14 of the numbers are available for the second row (one having been consumed for the first row). And that only 13, 12, and 11 numbers are available for each of the third, fourth, and fifth rows. Thus, the number of unique "B" (and "I", "G", and "O", respectively) columns is (15*14*13*12*11) = 360,360. The combinations of the "N" column differ due to the use of the free space. Therefore, it has only (15*14*13*12) = 32,760 unique combinations. The product of the five rows (360,3604 * 32,760) describes the total number of unique playing cards. That number is 552,446,474,061,128,648,601,600,000 simplified as 5.52×1026 or 552
septillion. Printing a complete set of Bingo cards is impossible for all practical purposes. If one
trillion cards could be printed each
second, a printer would require more than seventeen million
years to print just one set. However, while the number combination of each card is unique, the number of winning cards is not. If a winning game using e.g. row #3 requires the number set B10, I16, G59, and O69, there are 333,105,095,983,435,776 (333 quadrillion) winning cards. Therefore, calculation of the number of Bingo cards is more practical from the point of view of calculating the number of unique
winning cards. For example, in a simple one-pattern game of Bingo a winning card may be the first person to complete row #3. Because the "N" column contains a free space, the maximum number of cards that guarantee a unique winner is (15*15*15*15) = 50,625. Because the players need to only focus on row #3, the remaining numbers in rows #1, #2, #4, and #5 are statistically insignificant for purposes of game play and can be selected in any manner as long as no number is duplicated on any card. Perhaps the most common pattern set, known as "Straight-line Bingo" is completing any of the five rows, columns, or either of the main diagonals.
Other types of cards •
Break Open ==See also==