How many homes has Former President Jimmy Carter helped powering with clean energy?

Grade level: 4th – 6th grades

Skills: Multiplication (decimals)

sRelated environmental issues: Renewable Energy

Former President Jimmy Carter is a big supporter of renewable energy and helped a solar farm project which constructed as many as 3,850 of solar panels in his hometown in Georgia. He also installed 320 solar panels on the Jimmy Carter Presidential Library.


Plains Solar Farm, Georgia (Photo: Futurism)

  1. Each solar panel can power 1.3 American homes. How many homes can the solar farm power?
  2. How many homes can the solar panels on the Library power?
  3. How many homes has Former President Jimmy Carter helped powering with clean energy?



Note 1) The Plains solar farm generates 55 million kilowatt hours per year.

Note 2) The average annual electricity consumption for a U.S. residential utility customer was 10,766 kilowatthours (kWh). (U.S. Energy Information Administration)


Note 3) The numbers were slightly modified. The actual numbers of solar panels are 3,852 and 324.





Answer keys

  1. 5,005 homes    (3,850 x 1.3 = 5,005)
  2. 416 (320 x 1.3 = 416)
  3. 5,421 homes (5,005 + 416 = 5,421)

How many non-native marine species were found in Galápagos islands?

Grade level: 6th grades

Skills: Percentage and addition

sRelated environmental issues: Biodiversity

The Galápagos islands, which lie in the equatorial Pacific, have long been recognized for their remarkable biodiversity and their large number of endemic species.  However,  the environment of the Galápagos islands started to change because many non-native species have been brought to the islands by human activity over the last 500 years.


A recent research identified 53 non-native marine species in the islands.

  1. The research showed that 93% of the 53 species were likely brought to the Galápagos Islands by ships. How many non-native marine species were brought by ships? Round to the nearest whole number.
  1. The Galápagos islands were first visited by Europeans in the 1500s. By the late 1960s, 2000–3000 people lived on the Islands. In a 2010, there were 25,000 residents and one-quarter million visitors annually. Together, how many residents and tourists a year are there in the Galápagos islands?


Answer keys

  1. 49 species (53 x 0.93 = 49.29)
  2. 275,000 (25,000 + 250,000= 275,000)