75-Ball Bingo

The five columns are headed B, I, N, G and O, and each draws its numbers from its own range: B from 1 to 15, I from 16 to 30, N from 31 to 45, G from 46 to 60 and O from 61 to 75. Every column holds five numbers except N, which holds four because its middle cell is the free space. When a caller says a number, the letter in front of it tells you which column to look in.

The free space counts as marked from the first call, and it sits on 4 of the 12 possible lines: the middle row, the middle column and both diagonals. Those lines need only four numbers, which is why a line comes a little sooner than a shape of five would suggest.

The key number: One card makes its first line after 41.37 calls on average; ignore the free space and the same card needs 43.55.

Hard way means a line that does not use the free space, one of the 8 lines that avoid the center. Two and three lines share cells where they cross, so the numbers needed depend on which lines they are.

What sets 75-ball apart from the British game is the pattern. Halls vary the winning shape from game to game, from four corners and the postage stamp to letters, frames and the coverall, and a single session often runs through many of them. The shape is shown on a board before the first number is called, and only that shape wins.

Longer shapes stretch a game toward the end of the draw, and a coverall with a call limit is the usual route to a large jackpot. Each shape, with the calls it takes on one card, is ranked on the bingo patterns page.

Each full column chooses five of its fifteen numbers and the N column four, and the choices multiply. Counting only which numbers go in each column, there are 111,007,923,832,370,565 different cards. Counting the order down each column as well, as a printed card does, the number rises to 552,446,474,061,128,648,601,600,000.

In practice a hall plays from a printed series of cards, often a few thousand long, and the count shows why a series never runs short: the supply of different cards is effectively endless, and two players holding the same card is a matter of the printed series, never of chance.

Outside North America, 75-ball is a standard room in online bingo, often running alongside 90-ball games. Every game is staked, because the cards sold are what pay the prize. The free library is video bingo only, a single-player game with a fixed draw and a pattern table, described on the video bingo page and open to try on the free bingo games page.