<span>So we need to explain how we know 21/30 is greater than 2/3. Well lets expand 2/3 by multiplying the numerator and the denumerator by 10. That way we get 20 / 30. Since 21/30 has 1/30 more than 20/30 we can clearly see that 21/30 is greater than 20/30 or 2/3.</span>
Answer:
Step-by-step explanation:
a)
d=0.68t + 1.5 if t time is 3 hrs
d=0.68(3) + 1.5
= 2.04 + 1.5
d= 3.54 ft
b)
d=0.68t + 1.5 if d depth is 4 ft solve for t
d - 1.5 = 0.68t
(d - 1.5) / 0.68 = t
(4 - 1.5) / 0.68 = t
t = 2.5/0.68
t = 3.68 ft
c) I needed to bury my moth..... cat.
Answer:
a)
X | 1 3 5 7
f(X) | 0.4 0.2 0.2 0.2
b) 
Step-by-step explanation:
For this case we have defined the cumulative distribution function like this:





And we know that the general definition for the distribution function is given by:

Where f represent the density function.
Part a
For this case we need to find the density function, so we can find the values for the density for each value of X = 1,2,3,4,5,6,7,... since X is a discrete random variable.







And for any value higher than 7 we have that:
![x_i \in [8,9,10,...]](https://tex.z-dn.net/?f=%20x_i%20%5Cin%20%5B8%2C9%2C10%2C...%5D)

So then we have our density function defined like this:
X | 1 3 5 7
f(X) | 0.4 0.2 0.2 0.2
Part b
For this case we want to find this probability 
And since the random variable is discrete we can write this like that:

It's a little blurry could you try and take a more clear picture?
Answer:
(8x7y3)*(2/3*y)^2=32/9x7y5
Step-by-step explanation: