Question

A culture of bacteria is growing at a constant rate of 5% an hour. If the culture started with 3000 bacteria at 6:00 a.m. on Tuesday, calculate the approximate time that the bacteria population will reach 72,000?

Answer 1

`72,000 = 3000xx(1+0.05)^x` solve for`" " x" "`(hours from the start) and add them to the 06:00 start time and day.

Explanation:

The equation for exponential growth is:
`y = a(1+r)^x`
Where:
a = initial amount before measuring growth
r = growth/decay rate (often a percent)
x = number of time intervals that have passed