Answer:
C
Step-by-step explanation:
the Sq root for 156 HAS to be a # between 12 and 13.
12+ (13-12)/2
12+ 1/2
12.5
Answer:
13.53% probability that no earthquakes with a magnitude of 6.5 or greater strike the San Francisco Bay Area in the next 40 years
Step-by-step explanation:
In a Poisson distribution, the probability that X represents the number of successes of a random variable is given by the following formula:

In which
x is the number of sucesses
is the Euler number
is the mean in the given time interval.
According to geologists, the San Francisco Bay Area experiences five earthquakes with a magnitude of 6.5 or greater every 100 years.
One earthquake each 100/5 = 20 years.
What is the probability that no earthquakes with a magnitude of 6.5 or greater strike the San Francisco Bay Area in the next 40 years?
40 years, so 
This probability is P(X = 0).


13.53% probability that no earthquakes with a magnitude of 6.5 or greater strike the San Francisco Bay Area in the next 40 years
Answer:
as discriminant = 9, it has two real solutions.
Step-by-step explanation:
for eqn ax^2 + bx + c, discriminant = b^2 - 4ac
y = 4x^2 - 5x + 1
discriminant = (-5)^2 - 4(4)(1)
= 25 - 16
= 9
as discriminant > 0, it has two real solutions.
If we want to find when the population of species A will be equal to the population of species B, we need to see when the two equations for the population of each species are equal, ie. equate them and solve for t. Thus:
2000e^(0.05t) = 5000e^(0.02t)
(2/5)e^(0.05t) = e^(0.02t) (Divide each side by 5000)
2/5 = e^(0.02t) / e^(0.05t) (Divide each side by e^(0.05t))
2/5 = e^(-0.03t) (use: e^a / e^b = e^(a - b))
ln(2/5) = -0.03t (use: if b = a^c, then loga(b) = c )
t = ln(2/5) / -0.03 (Divide each side by -0.03)
= 30.54 (to two decimal places)
Therefor, the population of species A will be equal to the population of species B after 30.54 years.
I wasn't entirely sure about the rounding requirements so I've left it rounded to two decimal places.
Answer: 751 points
Step-by-step explanation:
454 + 297 = 751