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. Exponential equation
    exp In the set R solve the equation: ?
  3. Log
    log if ?, what is b?
  4. 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%?
  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. Logarithm
    log_hat Determine the number whose decimal logarithm is -3.8.
  7. Intercept with axis
    log_10 F(x)=log(x+4)-2, what is the x intercept
  8. Sequence
    seq Calculate what member of the sequence specified by ? has value 86.
  9. Exponential equation
    exp Solve exponential equation (in real numbers): 98x-2=9
  10. Coordinate
    exp_ln Determine missing coordinate of the point M [x, 120] of the graph of the function f bv rule: y = 5x
  11. 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
  12. Powers 3
    exp_4 2 to the power of n divided by 4 to the power of -3 equal 4. What is the vaule of n?
  13. Compound interest
    exponential_usd Calculate time when deposit in the bank with interest 2.5% p.a. doubles.
  14. Car value
    car_old The car loses value 15% every year. Determine a time (in years) when the price will be halved.
  15. Seats
    divadlo_2 Seats in the sport hall are organized so that each subsequent row has five more seats. First has 10 seats. How many seats are: a) in the eighth row b) in the eighteenth row
  16. Log
    exp_log Calculate value of expression log |3 +7i +5i2| .
  17. AS sequence
    AP In an arithmetic sequence is given the difference d = -3 and a71 = 455. a) Determine the value of a62 b) Determine the sum of 71 members.