WASHINGTON -- By the year 2030 the world will have nearly 3 billion more people in it than it has now, 2 billion of them in countries where the average person earns less than $2 a day, the World Bank predicts.


It estimates that the global figure will reach 8,474,017,000, compared with 5,692,210,000 in 1995. People will live longer, too. The average African baby born today can expect to live until 54.


"Who will feed and house these people?" asked the bank president, Lewis T. Preston. "The task is daunting, but it can be accomplished."


Its estimate came in advance of next month's United Nations conference on population in Cairo. It is expected to be the scene of a major debate on abortion and birth control, with the Vatican and some governments of some Catholic countries vehemently opposed to these measures.


Preston saw family planning as the way to break the cycle of poverty and rapid population growth.


"The solution to the problem can only come ... when couples, mostly in the developing countries, decide for themselves that smaller families are in their own best interest," he said.


The bank does not see any major effect yet from billions of dollars spent on promoting family planning. But it says action now on contraception and education can have a major impact after 2050.


It has found that sending more girls to school results in fewer babies later.