Find the sum of the first 30 terms for the given arithmetic sequence.
1 answer:
You might be interested in
Answer:
The probability of the sample mean foot length less than 23 cm is 0.120
Step-by-step explanation:
* Lets explain the information in the problem
- The eighth-graders asked to measure the length of their right foot at
the beginning of the school year, as part of a science project
- The foot length is approximately Normally distributed, with a mean of
23.4 cm
∴ μ = 23.4 cm
- The standard deviation of 1.7
∴ σ = 1.7 cm
- 25 eighth-graders from this population are randomly selected
∴ n = 25
- To find the probability of the sample mean foot length less than 23
∴ The sample mean x = 23, find the standard deviation σx
- The rule to find σx is σx = σ/√n
∵ σ = 1.7 and n = 25
∴ σx = 1.7/√25 = 1.7/5 = 0.34
- Now lets find the z-score using the rule z-score = (x - μ)/σx
∵ x = 23 , μ = 23.4 , σx = 0.34
∴ z-score = (23 - 23.4)/0.34 = -1.17647 ≅ -1.18
- Use the table of the normal distribution to find P(x < 23)
- We will search in the raw of -1.1 and look to the column of 0.08
∴ P(X < 23) = 0.119 ≅ 0.120
* The probability of the sample mean foot length less than 23 cm is 0.120
<u><em>Answer:</em></u>
The bird is approximately 9 ft high up in the tree
<u><em>Explanation:</em></u>
The required diagram is shown in the attached image
Note that the tree, the cat and the ground form a right-angled triangle
<u>Therefore, we can apply special trigonometric functions</u>
<u>These functions are as follows:</u>
<u>Now, taking a look at our diagram, we can note the following:</u>
α = 25°
The opposite side is the required height (x)
The adjacent side is the distance between the cat and the tree = 20 ft
Therefore, we can use the <u>tan function</u>
<u>This is done as follows:</u>
which is 9 ft approximated to the nearest ft
Hope this helps :)
The answer is C
it's easier if you graph it
we know that the x of the unknown vertice is 4, because this is a rectangle and that vertices has to be on the same x line as the point below.
y of the unknown vertice has to be 1 because the vertice to the left needs to be on the same y line as the unknown vertice
it's easier if you graph it
we know that the x of the unknown vertice is 4, because this is a rectangle and that vertices has to be on the same x line as the point below.
y of the unknown vertice has to be 1 because the vertice to the left needs to be on the same y line as the unknown vertice