Answer:
Ok, an exponential decay is written as:
P(t) = A*(1 - r)^t
Where A is the initial population, r is the rate of decay and t is the unit of time.
We know that the initial population is 15g
then:
P(t) = 15g*(1 - r)^t
And at t = 3hs, the populations is 5g
P(5h) = 5g = 15g*(1 - r)^5
5/15 = 1/3 = (1 - r)^5
(1/3)^(1/5) = (1 - r) = 0.8
Now, the half life time of the sustance is t = x, such that the population reduces to it's half:
P(x) = A/2 = 15g/2 = 7.5g
Then:
7.5g = 15g*0.8^x
7.5g/15g = 1/2 = 0.8^x
Now, remember that if we have:
a = b^x
then
x = ln(a)/ln(b)
ln(1/2)/ln(0.8) = x = 3,11 hours
Answer:
y = -x + 8
Step-by-step explanation:
m = -1 ; x1 = 3 ; y1 = 5
Slope point form: y - y1 = m(x -x1)
y - 5 = -1(x - 3)
y - 5 = -1x - 3 *(-1)
y - 5 =-x + 3
y = -x + 3 + 5
y = -x + 8
Step-by-step explanation:
A = A₀ ½^(t / T)
where A is the amount left, A₀ is the original amount, t is time, and T is the half life.
4 days is 96 hours, so the amount left is:
A = 600 ½^(96 / 15)
Answer:
(8x - 5) • (4x + 5)
Step-by-step explanation:
The answer you want is going to be A)
, because all you have to do is add the exponents which -4+-10 would be -14 so therefore the answer you want is going to be A)
