Nearly 50 residents of the gutted Greenbelt Plaza apartment complex appealed for help to the City Council Monday. Last week more than 15 families were displaced from the complex when fire ripped through the building at 11 Parkway Road, causing an estimated $200,000 in damage. Fire officials said the blaze was caused by a defective furnace on the third floor of the building.

Dennis Gottesmann, an attorney representing several residents, said "we are looking into the cause of the fire."

County Council Member Roy Dabney Jr. said he would ask several Prince George's agencies to help the displaced families.

In other business, the council held a public hearing as part of the process of distributing about $70,000 in city funds.

Four groups asked for appropriations. The Greenbelt CPR Committee wants $1,000 for equipment; the Aquatic Boosters Club requested $1,100 for swimming pool ropes; the Fraternal Order of Police asked for $5,000 for telephone tape-recording equipment for the city police; and the Greenridge House Tenants Association--a home for the handicapped and elderly--requested an unspecified amount for a public address system.

The council also increased the tax on coin-operated amusement devices from 4 1/2 to 10 percent of the machine revenue and introduced an ethics code for elected and appointed officials and city employes.