Answer:
The minimum sample size is 1867 observations.
Step-by-step explanation:
We need to construct an 85% confidence interval that has an error less than 0.06. It means that the difference between the upper limit (UL) and the lower limit (LL) has to be 0.06.
The only variable we can adjust is the number of observations (n)
For a 85% confidence interval, the z-score is 1.440.
The estimated variance (s^2) is 0.81.
The error e is 0.06.
The sample has to be at least of 1867 observations.
Answer:
Y = (0, 3)
Step-by-step explanation:
Notice that the first the transformation is a rotation of 90 degrees around the origin, and then a reflection around the x axis.
If a reflection around the x axis resulted in (3, 0) that means the point was already on the x axis.
Then in order for a rotation in 90 degrees to take the point Y to (3, 0), Y must have been on the y-axis as (0, 3)
Answer:
C. 18 cm
Step-by-step explanation:
The ratio of the sides of the triangle shown is 12 : 15 = 4 : 5. We know it is a right triangle, so we know the missing side length completes the ratio
3 : 4 : 5 = 9 : 12 : 15
Half of XY is 9 cm, so the length of the entire chord is 18 cm.
_____
The chord is tangent to the inner circle, so makes a 90° angle with the radius to that tangent point. This tells you that the triangle shown is a right triangle. It also tells you that the short radius bisects the chord. The Pythagorean theorem can be used to find the length of the side not shown (half the chord length).
The unknown side (a) can be found from ...
15² = 12² +a²
225 -144 = a² . . . . . . subtract 12²
81 = a² . . . . . . . . . . . simplify
9 = a . . . . . . . . . . . . . take the square root
The chord length is 2a, so is ...
2(9 cm) = 18 cm . . . . length of chord XY
Answer:
12
Step-by-step explanation:
It has been going down by 6 because 24-6=18 and 18-6=12.
