Question

When an antibiotic is introduced into a culture of 70,000 bacteria, the number of bacteria decreases at a continuous rate. After 5 hours, there are only 40,000 bacteria. Determine the the continuous rate. Round your answer to the nearest tenth of a percent. Use a positive sign if it is a continuous growth rate or negative sign if it is a continuous decay rate. Do not write the percent sign in your response.

Answer 1

- 10.6 % per hour

Explanation:

By 'continuous rate' I assume you mean linear bacteria/hour

40 000 - 47 000 = - 30 000 bacteria in 5 hours

- 30 000 bacteria / 5 hours = - 6000 bacteria per hour

But then you ask for percentage....so maybe you want an exponential rate

then 40 000 = 70 000 ( 1 - x)^5

where x = decimal percentage , 5 = years

solve for x = 10.588 % DECREASE per hour