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3 years ago

9

normally distributed with an unknown population mean and a population standard deviation of 4.5 points. A random sample of 45 sc

ores is taken and gives a sample mean of 84. Find a 90% confidence interval

1 answer:

shusha [124]3 years ago

3 0

Answer:

= ( 82.90, 85.10) points

Therefore at 90% confidence interval (a,b)= ( 82.90, 85.10) points

Step-by-step explanation:

Confidence interval can be defined as a range of values so defined that there is a specified probability that the value of a parameter lies within it.

The confidence interval of a statistical data can be written as.

x+/-zr/√n

Given that;

Mean x = 84

Standard deviation r = 4.5

Number of samples n = 45

Confidence interval = 90%

z(at 90% confidence) = 1.645

Substituting the values we have;

84+/-1.645(4.5/√45)

84+/-1.645(0.670820393249)

84+/-1.10

= ( 82.90, 85.10) points

Therefore at 90% confidence interval (a,b)= ( 82.90, 85.10) points

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3 years ago

Differentiate y=x⁴(1-2x⁵)⁶(5-8x³)².

Liula [17]

Step-by-step explanation:

Let $y(x)=f(x)g(x)h(x)$ where

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so that

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Recall that the derivative of the product of functions is

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so taking the derivatives of the individual functions, we get

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So the derivative of y(x) is given by

$y'(x) = 4x^3(1 -2x^5)^6(5 - 8x^3)^2 + x^4 6(1 -2x^5)^5(-10x^4)(5 - 8x^3)^2 + x^4(1 -2x^5)^6 2(5 - 8x^3)(-24x^2)$

or

$y'(x) = 4x^3(1 -2x^5)^6(5 - 8x^3)^2$

$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:- 60x^8(1 -2x^5)^5(5 - 8x^3)^2$

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3 years ago

SEND HELP YO Find and simplify the area (You need to completely multiply it out and include units in your answer):

Ad libitum [116K]

Answer:

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Step-by-step explanation:

Given

$Base = 2m^4 - 3$

$Height = 2m^4 - 3$

Required

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This is calculated as:

$Area = 0.5 * Base * Height$

$Area = 0.5 * (2m^4 - 3) * (2m^4 - 3)$

Open brackst

$Area = 0.5 * (4m^8 - 6m^4 - 6m^4 + 9)$

$Area = 0.5 * (4m^8 - 12m^4 + 9)$

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5 0

3 years ago

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Semmy [17]

Answer:

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Step-by-step explanation:

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3 years ago

Read 2 more answers

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Arada [10]

Answer:

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Step-by-step explanation:

Use the square of a binomial theorem

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Now expand the given equation:

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Hope this helps :)

Have a great day!

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3 years ago