Zambia is 3.1 times larger than Uganda.
Area: 241,038 km2 World Factbook
Population: 35,918,915 (July 2014) World Factbook
Uganda, officially the Republic of Uganda, is a landlocked country in East Africa. It is bordered on the east by Kenya, on the north by South Sudan, on the west by the Democratic Republic of the Congo, on the southwest by Rwanda, and on the south by Tanzania. Wikipedia
Area: 752,618 km2 World Factbook
Population: 14,638,505 (July 2014) World Factbook
The Republic of Zambia is a landlocked country in Southern Africa, neighboring the Democratic Republic of the Congo to the north, Tanzania to the north-east, Malawi to the east, Mozambique, Zimbabwe, Botswana and Namibia to the south, and Angola to the west. Wikipedia