Answer:
0.02275
Step-by-step explanation:
We have been given that the time needed to complete a final examination in a particular college course is normally distributed with a mean of 80 minutes and a standard deviation of 10 minutes. We are asked to find the probability of completing the exam in one hour or less.
We know that 1 hour equals 60 minutes. First of all, we will find the z-score corresponding to 60 minutes.

z = z-score,
x = Sample score,
= Mean,
= Standard deviation.



Now, we will use normal distribution table to find area under z-score of
as:


Therefore, the probability of completing the exam in one hour or less is 0.02275.
Given two functions are
f(x) = 2 cos(x)
g(x) = 3 sin(x+
)
We know that the maximum value of cos x and sin x is always 1
y= maximum of cos = 1
y= maximum of sin =1
f(x) = 2 cos(x)
y= 2 (max of cos) = 2(1) = 2
g(x) = 3 sin(x+
)
y= 3 (max of sin) = 3(1) = 3
g(x) = 3 sin(x+
) has the maximum value.
Let x be the common factor between chickens and ducks. Then:
6x/(5x-63)=3/1
15x-189=6x
9x=189
x=21
6x=123 chickens were on the farm
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