Chapter 2.1, Problem 131E

ACHIEVING SUCCESS

According to the Ebbinghaus retention model, you forget 50% of what you learn within one hour. You lose 60% within 24 hours, After 30 days. 70% is gone. Reviewing previously covered topics is an effective way to counteract this phenomenon. From here on, each Exercise Set will contain three review exercises. It is essential to review previously covered topics to improve your understanding of the topics and to help maintain your mastery of the material. If you are not certain how to solve a review exercise, turn to the section and the worked example given in parentheses at the end of each exercise. The more you review the material, the more you retain. Answers to all Retaining the Concepts Exercises are given in the answer section.

Sharks may be scary, but they are responsible for only three deaths worldwide in 2014. The world's deadliest creatures, ranked by the number or human deaths per year, are mosquitoes, snails, and snakes. The number of deaths by mosquitoes exceeds the number of deaths by snakes by 661 thousand. The number of deaths by snails exceeds the number or deaths by snakes by 106 thousand. Combined, mosquitoes, snails, and snakes result in 1049 thousand (or 1,049,000) human deaths per year. Determine the number of human deaths per year, in thousands, by snakes, mosquitoes, and snails. (Source; World Health Organization) (Section 1.3, Example 1)