On the first day of a measles outbreak at a school, 6 students were identified to have the measles. Each day for the following two weeks, the number of new cases doubled from those identified with the disease the previous day.

How many total students are identified to have measles at the end of the 6th day of the outbreak?

cassihasty
May 17, 2018

#1**+1 **

We have this equation

Total on day 6 = initial value * [ 1 - common ratio^number of days ] / [ 1 - common ratio]

The initial value is 6

The common ratio is 2 [ the ratio "doubles" the number each day ]

The number of days = 6

So....

Total on day 6 = 6 [1 - 2^6] /[1 - 2 ] =

6 [ 1 - 64] / [-1] =

6 [ 64 - 1] =

6 [63] =

378 total students on at the end of day 6

CPhill
May 17, 2018