Answer:
The last one
Step-by-step explanation:
You start off with 50.
It says the water is being drained so the slope is negative.
Answer: if u where doing 8x-11 that would = -88
Step-by-step explanation:
Answer:
<h2>x = 117°</h2>
Step-by-step explanation:
We know:
The sum of the quadrilateral angles measures 360°.
Therefore we have the equation:
The sum of angles x and D is equal to 360°. Therefore we have the other equation:
From (1) and (2) we have:
Answer:
It travel at the rate of <u>500 miles per hour</u>.
Step-by-step explanation:
Given:
Ewans flight is scheduled to travel 1,750 miles in 3.5 hours.
Now, to find the rate it travel per hour.
Distance = 1,750 miles.
Time = 3.5 hours.
So, to get the rate we put formula:
Therefore, it travel at the rate of 500 miles per hour.
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
