pre-calc

posted by .

The probability, P, in percent, that a person will respond to a certain ad can be modelled by the equation P(n)=1-2^(-0.05n), where n is the number of days since the ad began on tv. After how many days is the probability greater than 20%?

my work:
0.20=1-2^(-0.05n)

then i solved for n, but i got a negative number.. what is wrong with my equation that i made and why

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. pre calc

    Over the course of a year, the number of hours of daylight in Australia is modelled by H=12+3 cos(2pi/365 *t) where t is the time in days and T is the number of daylight.
  2. Chemistry

    a) 45.02% of the sample remains after 85 days. Consider how you can use the percent of Ir-192 remaining and the number of days to calculate the mass remaining after 85 days.
  3. statistics

    The number of vacation days taken by employees of a company is normally distributed with a mean of 14 days and a standard deviation of 3 days. For the next employee, what is the probability that the number of days of vacation taken …
  4. MAT 201

    The number of vacation days taken by employees of a company is normally distributed with a mean of 14 days and a standard deviation of 3 days. For the next employee, what is the probability that the number of days of vacation taken …
  5. statistics

    The number of vacation days taken by employees of a company is normally distributed with a mean of 14 days and a standard deviation of 3 days. For the next employee, what is the probability that the number of days of vacation taken …
  6. Pre-Calc

    A radioactive isotope has a half life of 8.1 days. If the sample starts with 25 grams, how much will there be after 90 days?
  7. Math

    the average employee in the united states works for about 248 days per year and receives abt 13 days of paid vacation. write the number of vacation days as a percent of the total number of days worked. round to the nearest 100th's …
  8. pre calc

    You have a sample of a certain radioactive substance. After two days, thirty percent of the sample has decayed. What is the half-life of the material and how much will have decayed after a week?
  9. pre calc

    You have a sample of a certain radioactive substance. After two days, thirty percent of the sample has decayed. What is the half-life of the material and how much will have decayed after a week?
  10. VSU

    Am influenza epidemic hits. large city and spreads at the rate of 12e^0.2t new cases per day, where t is the number of days since the epidemic began. The epidemic began 4 cases. find the number of cases during the first 30 days.

More Similar Questions