Solve the problem.
-Doctors predict that by administering a vaccine, the number of new cases of a certain childhood disease will decrease by half each year. If 1000 people were afflicted with the disease in 2010,Estimate the number of new cases in 2015. (Round to the nearest whole number, if necessary.)
A) 63 new cases
B) 31 new cases
C) 16 new cases
D) 125 new cases

Question

Quizplus · Accepted Answer

The number of cases decreases by half each year. Starting with 1000 cases in 2010, the sequence is: 2011: 500, 2012: 250, 2013: 125, 2014: 62.5, 2015: 31.25. Rounding 31.25 gives 31 new cases in 2015.

Solve the Problem. -Doctors Predict That by Administering a Vaccine, the Number of the Number