Pineapple Tapioca

Drain juice from one large can of pineapple into measuring cup. Add equal amount of water and put juice and water in double boiler. After hot add 1/2 cup of minute tapioca. Let it cook until tapioca is dissolved. Remove from double boiler and add 3/4 cup sugar. When cool add diced pineapple and just before serving fold in 1/2 pint whipped cream.