The NW Shopping Mall conducts special events to attract potential patrons. Among the events that seem to attract teenagers, the young/middle-aged group, and senior citizens, the two most popular are band concerts and art shows. Their costs per presentation are

$1500 and $3000, respectively. The total (strict) annual budget allocated to the two events is $20,000. The mall manager estimates the attendance as follows:

Number attending per presentation Event Teenagers Young/middle-age Seniors Band concert 200 100 0 Art show 0 400 250 The manager has set minimum goals of 1500, 450, and 900 for the attendance of teenagers, the young/middle-aged group, and seniors, respectively. Formulate the problem as a goal programming model.