Say that a town has 1,000 residents, of whom 60% are women, 40% are men. Of the women, 40% wear one earring. Half of the rest wear two earrings, and half wear none. Of the men, 60% wear one earring. Half of the rest wear two earrings, and half wear none. How many earrings are being worn in all?

Hint. This problem can be solved with virually no calculations.

Source: *Source: Parade, Ask Marilyn, Jan. 14, 2007*