William R. Day, Sr. of Oxford, Miss. and Deana Doss Day of Springdale, Ark. announce the engagement of their daughter, Maggie Martha Day to Nicolas Elliott Brito, son of Dr. and Mrs. Cesar Gilberto Brito of Paradise Valley, Ariz. Miss Day is the granddaughter of David W. and the late Sue H. Doss of Fayetteville, and J. Donald and the late Martha H. Day of Vicksburg, Miss. Mr. Brito is the grandson of Dr. Raul Brito of Quito, Ecuador, Martha Peñaherrera and the late Mr. and Mrs. Rex Hearst of Prairie Village, Kansas. Miss Day, a graduate of Fayetteville High, the University of Mississippi, and London School of Economics, is a journalist in London. Mr. Brito, a graduate of Brophy College Preparatory in Phoenix, Ariz., and the University of Southern California, is an investor in London. The wedding is May 12th in Ravello, Italy.