Post a New Question


posted by .

assume the half-life of the substance is 31 days and the initial
amount is 183.9 grams.

(a) Fill in the right hand side of the following equation which expresses
the amount A of the substance as a function of time t (the coefficient of t in the exponent should have at least four significant digits):

(b) When will the substance be reduced to 2.4 grams?

(use decimals.)

  • calculus -

    There is not "followiong equation" to fill in.

    Amount left = 183.9*2^(-t/31)

    You don't need 4 sig figs in the exponent in this form if the half life is exactly 31 days.

    (b) When amount left = 2.4,
    2.4/183.9 = 0.01088 = 2^(-t/31)
    -4.5212 = (-t/31)*ln 2 = -0.02236t
    t = 202.2 days

  • calculus -

    the second answer is 194.052 days

Answer This Question

First Name:
School Subject:

Related Questions

More Related Questions

Post a New Question