Answer and explanation:
There are six main trigonometric ratios, namely: sine, cosine, tangent, cosecant, secant, cotangent.
Those ratios relate two sides of a right triangle and one angle.
Assume the following features and measures of a right triangle ABC
- right angle: B, measure β
- hypotenuse (opposite to angle B): length b
- angle C: measure γ
- vertical leg (opposite to angle C): length c
- horizontal leg (opposite to angle A): length a
- angle A: measure α
Then, the trigonometric ratios are:
- sine (α) = opposite leg / hypotenuse = a / b
- cosine (α) = adjacent leg / hypotenuse = c / b
- tangent (α) = opposite leg / adjacent leg = a / c
- cosecant (α) = 1 / sine (α) = b / a
- secant (α) = 1 / cosine (α) = b / c
- cotangent (α) = 1 / tangent (α) = c / b
Then, if you know one angle (other than the right one) of a right triangle, and any of the sides you can determine any of the other sides.
For instance, assume an angle to be 30º, and the lenght of the hypotenuse to measure 5 units.
- sine (30º) = opposite leg / 5 ⇒ opposite leg = 5 × sine (30º) = 2.5
- cosine (30º) = adjacent leg / 5 ⇒ adjacent leg = 5 × cosine (30º) = 4.3
Thus, you have solved for the two unknown sides of the triangle. The three sides are 2.5, 4.3, and 5.
Answer:
The 95% confidence interval estimate for the true proportion of adults residents of this city who have cell phones is (0.81, 0.874).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
For this problem, we have that:

95% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
The lower limit of this interval is:

The upper limit of this interval is:

The 95% confidence interval estimate for the true proportion of adults residents of this city who have cell phones is (0.81, 0.874).
It has to be 36 because it the same stick as the other stick that is telling 36