Radioactivity

After 548 hours decreases the activity of a radioactive substance to 1/9 of the initial value. What is the half-life of the substance?

Result

t1/2 =  172.9 hours

Solution:

Solution in text t__1/2 =







Leave us a comment of example and its solution (i.e. if it is still somewhat unclear...):

Showing 0 comments:
1st comment
Be the first to comment!
avatar




To solve this example are needed these knowledge from mathematics:

Next similar examples:

  1. Theorem prove
    thales_1 We want to prove the sentense: If the natural number n is divisible by six, then n is divisible by three. From what assumption we started?
  2. The city 3
    city_2 The city has 22,000 residents. How long it is expected to have 25,000 residents if the average annual population growth is 1.4%?
  3. Exponential equation
    exp In the set R solve the equation: ?
  4. Log
    log if ?, what is b?
  5. Water lilies
    lekno_2 Water lilies are growing on the pond and their number is doubled every day. The whole layer is covered in 12 days. How many days will it cover 8 layers?
  6. Intercept with axis
    log_10 F(x)=log(x+4)-2, what is the x intercept
  7. Logarithm
    log_hat Determine the number whose decimal logarithm is -3.8.
  8. Coordinate
    exp_ln Determine missing coordinate of the point M [x, 120] of the graph of the function f bv rule: y = 5x
  9. Sequence
    seq Calculate what member of the sequence specified by ? has value 86.
  10. Computer revolution
    Intel386 When we started playing with computers, the first processor, which I remember was the Intel 8080 from 1974, with the performance of 0.5 MIPS. Calculate how much percent a year rose CPU performance when Intel 486DX from 1992 has 54 MIPS. What
  11. Exponential equation
    exp Solve exponential equation (in real numbers): 98x-2=9
  12. Car value
    car_old The car loses value 15% every year. Determine a time (in years) when the price will be halved.
  13. Compound interest
    exponential_usd Calculate time when deposit in the bank with interest 2.5% p.a. doubles.
  14. Wavelength
    wave_length Calculate the wavelength of the tone frequency 11 kHz if the sound travels at speeds of 343 m/s.
  15. Sequence 3
    75 Write the first 5 members of an arithmetic sequence: a4=-35, a11=-105.
  16. Simple interest 3
    coins-uk_1 Find the simple interest if 11928 USD at 2% for 10 weeks.
  17. Population
    population_2 What is the population of the city with 3% annual growth, if in 10 years the city will have 60,000 residents?