Mrs. Reid is going on a trip. She has 9 books that she hasn't read yet, but she wants to bring only 3 on the trip. In how many w
2 answers:
Answer:
Option B is right.
Step-by-step explanation:
Given that there are totally 9 books unread by Mrs. Reid. OUt of these she wants to take only 3 books on the trip.
For books order does not count.
Hence combinations would be appropriate to calculate.
3 books out of 9 can be selected in
9C 3 ways
No of ways of selecting 3 books for the trip out of 9 =
There are just 84 ways of choosing 3 books to bring on the trip out of 9 unread books.
Option B is right.
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The line of best fit is a straight line that can be used to predict the
average daily attendance for a given admission cost.
Correct responses:
- The equation of best fit is;
- The correlation coefficient is; r ≈<u> -0.969</u>
The given data is presented in the following tabular format;
The equation of the line of best fit is given by the regression line
equation as follows;
Where;
= Predicted value of the<em> i</em>th observation
b₀ = Estimated regression equation intercept
b₁ = The estimate of the slope regression equation
= The <em>i</em>th observed value
= 24.625
= 960.625
Therefore;
Therefore;
- The slope given to the nearest tenth is b₁ ≈ -4.9
By using MS Excel, we have;
n = 8
∑X = 197
∑Y = 7365
∑X² = 4939
∑Y² = 6782675
∑X·Y = 180930
(∑X)² = 38809
Therefore;
- The y-intercept given to the nearest tenth is b₀ ≈ 1,042
The equation of the line of best fit is therefore;
The correlation coefficient is given by the formula;
Where;
Which gives;
The correlation coefficient given to the nearest thousandth is therefore;
- <u>Correlation coefficient, r ≈ -0.969</u>
Learn more about regression analysis here:
Answer:
x = 2√2
y = 2√6
Step-by-step explanation:
Consider the ratio of the two legs of the two smaller interior right triangles. (refer to attached diagrams for the triangles - I have outlined one in blue and the other in red)
These will be equal since the triangles are similar
shorter leg : longer leg
(blue triangle = red triangle)
⇒ x : 4 = 2 : x
⇒ x/4 = 2/x
⇒ x² = 8
⇒ x = √8
⇒ x = 2√2
Now we have x, we have the two legs of the right triangle with hypotenuse labelled y.
Using Pythagoras' Theorem a² + b² = c² (where a and b are the legs and c is the hypotenuse)
⇒ 4² + (2√2)² = y²
⇒ y² = 24
⇒ y = √24
⇒ y = 2√6
