A culture started with 1,000 bacteria. After 3
hours, it grew to 1,100 bacteria. Predict how
many bacteria will be present after 17 hours.
Round your answer to the nearest whole
number.

Respuesta :

1717 bacteria will be present after 17 hours

Solution:

The exponential growth function is given as:

[tex]y = a(1+r)^t[/tex] --------- eqn 1

Where,

y is future value

a is initial value

r is growth rate in decimal

t is time period

A culture started with 1,000 bacteria. After 3  hours, it grew to 1,100 bacteria

Therefore,

Substitute a = 1000, y = 11000 and t = 3 in eqn 1

[tex]1100 = 1000(1 + r)^3\\\\(1+r)^3 = \frac{1100}{1000}\\\\(1+r)^3 = 1.1\\\\Take\ cube\ root\ on\ both\ sides\\\\1 + r = \sqrt[3]{1.1} \\\\1 + r = 1.0323[/tex]

Predict how  many bacteria will be present after 17 hours.

Substitute a = 1000 and t = 17 and  1 + r = 1.0323 in eqn 1

[tex]y = 1000(1.0323)^{17}\\\\y = 1000 \times 1.716725\\\\y = 1716.725 \approx 1717[/tex]

Thus 1717 bacteria will be present after 17 hours