<span>Assuming the reaction is of 1st order, we can
start using the formula for rate of 1st order reaction:</span>
dN / dt = k * N
Rearranging,
dN / N = k dt
Where N = amount of sample, k = rate constant, t = time
Integrating the equation from N = Ni to Nf and t = ti to
tf will result in:
ln (Nf / Ni) = k (tf – ti)
Since k is constant, we can equate to situations.
Situation 1 is triple in size every days, situation 2 is after 20 days.
ln (Nf / Ni) / (tf – ti) = k
ln (3Ni / Ni) / 4 = ln (Nf / 40) / 20
Calculating for Nf,
<span>Nf =
9,720 bacteria </span>
Answer:
66.67% probability that all selected components function properly
Step-by-step explanation:
A probability is the number of desired outcomes divided by the number of total outcomes.
The order in which the components are chosen is not important. So we use the combinations formula to solve this question.
Combinations formula:
is the number of different combinations of x objects from a set of n elements, given by the following formula.
In this question:
Desired outcomes:
2 components which function properly, from a set of 5. So
Total outcomes:
2 components, from a set of 6. So
Probability:
66.67% probability that all selected components function properly
Y= 250000-8750t
3.5 percent of 250000 is 8750, if that’s the amount decreasing each (t) years, you multiply that number by number of years taken into account.
105 divided by 6 equals 17. 5
She should buy 18 packages
123/0.75 =164
the answer is 164
