Answer:

Step-by-step explanation:
We can use the pascal triangle to find the coefficients of the expasion of the cube. It holds that

Answer:

And we can find the individual probabilities like this:
And adding we got:

Step-by-step explanation:
Previous concepts
The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".
Let X the random variable of interest, on this case we now that:
The probability mass function for the Binomial distribution is given as:
Where (nCx) means combinatory and it's given by this formula:
Solution to the problem
For this case we want to find this probability:

And we can find the individual probabilities like this:
And adding we got:

5x + 2y = 7....multiply by -3
-2x + 6y = 9
----------------
-15x - 6y = -21 (result of multiplying by -3)
-2x + 6y = 9
---------------add
-17x = - 12
x = 12/17 or 0.7
5x + 2y = 7
5(12/17) + 2y = 7
60/17 + 2y = 7
2y = 7 - 60/17
2y = 119/17 - 60/17
2y = 59/17
y = 59/17 * 1/2
y = 59/34 or 1.7 when rounded <====
Answer: C
Step-by-step explanation:
This describes an expotential function
At t = 0, P = 70
Therefore, C = 70
P = 70 e^kt
Solve for k by plugging in (4,360)
k = 0.4094
plug in t(7 hours)
70 e^(0.4094*7)
The answer roughly equals C