Answer:
it is 4.2 n
Step-by-step explanation:
because you have to divide 525/125=4.2
Relations are ordered pair sets (x,y) mapping a value to another value
the set of 1st components is called the domain
the set of 2nd components is called the range
The length of the circle's radius = 744.92 cm
Given the length of arc of a circle, arc length = 269π cm
Central angle of a circle is the angle made between the radius through the arc length at the center of the circle.
The corresponding central angle = 65°
To find the corresponding central angle in radians = 65° x π/180 = 13π/36 radians
We have, arc length of a circle = radius x central angle
Therefore, radius of the circle = arc length / central angle
= 269π /(13π/36)
= 744.92 cm
Learn more about arc length of a circle at brainly.com/question/28108430
#SPJ4
Answer:
This means that we are 80% confident that the mean of the drive-through service time is between 178.0 seconds and 181.0 seconds. This conclusion was obtained after examined 576 customers. If you want a greater % of confidence you will have to lower the lower bound and increase the upper bound
Let's call our estimate x. It will be the average of n IQ scores. Our average won't usually exactly equal the mean 97. But if we repeated averages over different sets of tests, the mean of our estimate the average would be the same as the mean of a single test,
μ = 97
Variances add, so the standard deviations add in quadrature, like the Pythagorean Theorem in n dimensions. This means the standard deviation of the average x is
σ = 17/√n
We want to be 95% certain
97 - 5 ≤ x ≤ 97 + 5
By the 68-95-99.7 rule, 95% certain means within two standard deviations. That means we're 95% sure that
μ - 2σ ≤ x ≤ μ + 2σ
Comparing to what we want, that's means we have to solve
2σ = 5
2 (17/√n) = 5
√n = 2 (17/5)
n = (34/5)² = 46.24
We better round up.
Answer: We need a sample size of 47 to be 95% certain of being within 5 points of the mean
