Answer:
y^35
Step-by-step explanation:
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
The only answers that are possible is z=y-x y=x+z or x=y-z
Answer: 64 centimeters squared.
Step-by-step explanation: This shape is a parallelogram. And the area of a parallelogram is just the base multiplied by the height. Here, the base is 10 cm and the height is 7 cm. So you might think the the area is just 70 centimeters squared. But here's the catch. There is a rectangular region in this parallelogram that is not shaded. But you can still easily solve this problem. All you need to do is find the area of that rectangular region and you already know the length and the width of this region. And, remember, the area of a rectangle is just the length and the width multiplied. So here, the area of that rectangular region is just 2 cm multiplied by 3 cm. Which will give you 6 centimeters squared. Now, all that's left to do is subtract the area of that rectangular region, 6 centimeters squared, from the total area of the parallelogram, 70 centimeters squared. And that should give you 64 centimeters squared as your final answer. I really hope this makes sense and is helpful.
Answer:
Step-by-step explanation:
go to the left by two
