Legalized gambling is getting closer in the District of Columbia. The city's Lottery and Charitable Games Control Board asked gambling companies to submit proposals by April 30 for marketing four instant lottery games, the first to begin late in July or early in August.

Douglass Gordon, executive director for the board, said yesterday the city expects to sell about 10 million tickets at $1 apiece in the first three months of the lottery.

The city would expect to pocket about 30 percent, or $3.3 million, of the gross sales; prizes would account for 45 to 50 percent, up to $5 million, with the balance, perhaps $1.2 million, for the gambling company's expenses and profit.

Under the board's proposal, prospective bidders would propose names for the games, determine how much money each ticket would pay and how the tickets should be marketed.

The instant game will use "rub off" cards. They will be sold in an as-yet-undetermined number of outlets, although sales in Georgetown or the city's Federal Center are prohibited. In the more distant future is a daily numbers game that will be vended through a network of shops with computerized printout machines.