The Grand Canyon in northern Arizona is one of nature's marvels. In fact, it is considered one of the seven wonders of the world and was designated as a World Heritage Site in 1979. The Grand Canyon is a remarkable example of the power of erosion. The sedimentary rock layers that can be seen in the canyon were originally formed under ancient seas. The rock beneath the seas was uplifted and has been eroded over millions of years by the forces of wind and water. The Colorado River continues to cut deeper and deeper into the canyon.
The Grand Canyon was first explored by boat in 1869 by a party led by John Wesley Powell. Powell was an army major who lost an arm during the Civil War. Grand Canyon National Park was created in 1919 and includes 277 miles of the Colorado River. Visitors to the bottom of the Grand Canyon can observe rocks that are over 4 billion years old! The national park includes an amazing range of plant and animal communities. By traveling from the bottom of the canyon to the park’s tallest heights, you can experience floodplain, desert and alpine tundra ecosystems.
Suppose you and your family decide to take a rafting trip down the Colorado River through the Grand Canyon National Park. If you travel at a rate of 14 miles per day for one-half of the distance of your rafting trip and at a rate of 18 miles per day for the other half of the distance of your trip, how many days will it take you to travel through the Grand Canyon National Park? If you spend 8 hours a day on the river, how many hours will you spend on the raft? (Please answer to the nearest whole number of days and hours.)