uhhh… where’s the equation? lol
TLDR: 241 clients will be taking +3 vacations.
This is a common example of representative scale size, or sample size. In selecting a small amount of people at random from a larger group, one can estimate the amount of people in the large group picking a specific answer based on a smaller, but proportionate, group size.
In the sample size, 21 of the 45 tested people said that they would go on more than three vacations a year, and this scale is supposedly proportional to the total group. Therefore, we can use a simple proportion to estimate the amount of people who would also say that they are going on more than three trips a year:
21 would ‘N’ would
————— = ——————
45 total 516 total
where N represents the number of people in the big group that would go on more than three trips a year.
Solve the proportion by cross-multiplication:
45N = 10,836
N = 240.8 people, or 241 people.
Based on the sample data, 241 people out of the 516 total will be taking more than three vacations a year.
If you drew the two vectors for the velocity you find a triangle rectangle since the two directions East and North form an angle of 90°. I drew first the vector towards East and second the vector towards North.
Therefore, to get the speed relative to the surface you have to sum the two vectors, which means you can apply the Pythagorean theorem to find the hypotenuse, having the two legs.
h = √(4² + 12²) = √160 = 4√10 = 12.65mph
In order to find the direction, you need to use trigonometry:
- the sine of an angle is given by the ratio between the opposite side divided the hypotenuse;
- the cosine of an angle is given by the ratio between the adjacent side divided by the hypotenuse.
You can use either one, I will show you both:
sinα = O / H
inverting the formula: α = arcsin (O / H) = sin⁻¹ <span>(O / H)
these two forms are equivalent.
Similarly:
cos</span>β = A / H
β = arccos (A / H) = cos⁻¹ <span>(A / H).
Substituting your numbers:
</span>α = sin⁻¹ (12 / 12.65) = <span>sin⁻¹ (0.9486) = 1.25rad
</span>β = cos⁻¹ (4 / 12.65) = cos⁻¹<span> (0.3162) = 1.25rad
As you can see, </span>α = β so you can use either formula.
Your answer will then be: the child is moving relative to the surface of the water with a speed of 12.65mph at a direction of 1.25rad from East towards North.
ATTENTION!
If you drew first the vector towards North and then the one towards East, you get an equivalent triangle, which is rotated by 180° respect to the previous one. This way, what you earlier called Opposite is now Adjacent and vice-versa, but the formulas are still valid.
You will get:
α = sin⁻¹ (4 / 12.65) = <span>sin⁻¹ (0.3162) = 0.32rad
</span>β = cos⁻¹ (12 / 12.65) = cos⁻¹<span> (0.9486) = 0.32rad
And your answer will be: </span><span>the child is moving relative to the surface of the water with a speed of 12.65mph at a direction of 0.32rad from North towards East.</span>
The slope is 2 and the y-intercept is 4
Answer:
1/2
-1/2
Step-by-step explanation:
we know that
If a dilation produce a contraction that means that the absolute value of the scaling factor is less than 1
If a dilation produce an enlargement that means that the absolute value of the scaling factor is greater than 1
<u><em>Verify each case</em></u>
case 1) 2
----> is a enlargement
case 2) 1/2
----> is a contraction
case 3) -2
----> is a enlargement
case 4) -1/2
----> is a contraction
