Answer:
+49 feet
Step-by-step explanation:
The inicial position that Suzie started her hike was 220 feet below sea level, so as this inicial position was negative, let's use the negative sign for it:
Inicial position = -220 feet
The final position of the hike was 171 feet below sea level, so:
Final position = -171 feet
So we calculate the change in elevation from the beginning to the end of the hike by making the difference between the final position and the inicial position:
Change in elevation = Final position - Inicial position = -171 - (-220) = -171 + 220 = +49 feet
The change in elevation was +49 feet (the positive sign indicates that the movement was upwards, in direction to "above sea level")
Answer:
Mean: 0.400
Standard error: 0.022
Step-by-step explanation:
We are taking samples of size n=500 out of a population with parameter p=0.40.
The expected distribution is the sampling distribution of sampled proportions. This distribution has parameters that are calculated as:
Mean: the mean of the sampling distribution is equal to the population proportion, as it is not biased.
In this case, the mean of this sampling distribution is p=0.40.
Standard error: the standard error depends on the population proportion and the sample size. It is calculated as:

being p: population proportion, N: sample size.
Answer:

Step-by-step explanation:
Given the geometric sequence
-0.6, 3, -15, 75, ...
Common ratio, 
The next term,
is obtained by multiplying the previous term c(n-1) by -5.
Therefore, the recursive formula for the sequence is:

Probability of 1st number being even : 3/7
probability of 2nd number being even : 2/6
probability of 3rd number being even : 1/5
probability of all 3 numbers being even : 3/7 * 2/6 * 1/5 = 6/210 = 1/35