The quality control manager at a light bulb manufacturing company needs to estimate the mean life of the light bulbs produced at the factory. The life of the bulbs is known to be normally distributed with a standard deviation (sigma) of 80 hours. A random sample of 16 light bulbs indicated a sample mean life of 1000 hours. What is a 95% confidence interval estimate (CIE) of the true mean life (m) of light bulbs produced in this factory

Answers

Answer 1
Answer:

Answer: (960.80,1039.20)

Step-by-step explanation:

Let X denotes a random variable that represents the life of the light bulbs produced at the factory.

As per given,

\sigma=80\n\n n=16\n\n \overline{x}=1000

Critical z-value for 95% confidence interval : z* = 1.96

Confidence interval for population mean:

\overline{x}\pm z^*(\sigma)/(√(n))\n\n  =1000\pm (1.96)(80)/(√(16))\n\n=1000\pm 1.96*(80)/(4)\n\n=1000\pm 1.96*20\n\n=1000\pm39.2\n\n=(1000-39.2,\ 1000+39.2)\n\n=(960.80,1039.20)

So, a 95% confidence interval estimate (CIE) of the true mean life (m) of light bulbs produced in this factory = (960.80,1039.20)


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Which polygons have at least one pair of parallel sides but are not parallelograms? Choose all that apply.
Idk how to solve this find value of x and y
Simplify 2c+6d+4c-8c
Convert x2 + y2 = 16 to polar form.r = 16r = 4θ = 16θ = 4

Would give you brainliest whoever answers this correct first !!

Answers

6 is the answer to the question

HELP QUICK!!!L 18 16 12 10 4 32 34 36 38 40 14 46 54 50 08 The graph shows that as Fincreases, C o decreases increases is constant increases then decreases​

Answers

Answer:

increases

Step-by-step explanation:

Since the lines goes up as the variable F increases( F is the horizontal variable), C will increase

Answer:

The line increases because u can obviously see the line going up...

Step-by-step explanation:

(1 point) For the equation given below, evaluate ′ at the point (−1,2). (5−)^4+4^3=2433. ′ at (−1,2) =

Answers

Answer:

(343)/(71)

Step-by-step explanation:

Given the equation

(5x-y)^4+4y^3=2433

Find the derivative:

((5x-y)^4+4y^3)'=(2433)'\n \n4(5x-y)^3\cdot (5x-y)'+4\cdot 3y^2\cdot y'=0\n \n4(5x-y)^3\cdot (5-y')+12y^2y'=0

Substitute

x=-1\n \ny=2,

then

4(5\cdot (-1)-2)^3\cdot (5-y')+12\cdot 2^2\cdot y'=0\n \n4(-5-2)^3(5-y')+48y'=0\n \n4\cdot (-7)^3\cdot (5-y')+48y'=0\n \n-1,372(5-y')+48y'=0\n \n-6,860+1,372y'+48y'=0\n \n1,420y'=6,860\n \ny'=(6,860)/(1,420)=(686)/(142)=(343)/(71)

Simplify The square root of 5 (6-4 the square root of 3)

Answers

Answer:

7.75

Step-by-step explanation:

6-4=2

2 times the square root of 3=3.46410161514

square root of 5 times 3.46410161514=7.74596669242

to 2dp=7.75

When a water-cooled nuclear power plant is in operation, oxygen in the water is transmuted to nitrogen-17. After the reactor is shut down, the radiation from the nitrogen-17 decreases in such a way that the rate of change in the radiation level is directly proportional to the radiation level.Required:
Write a differential equation that expresses the rate of change in the radiation level in terms of the radiation level.

Answers

Answer:

The differential equation is (dR)/(dt) = -kR

Step-by-step explanation:

Differential equation for the rate of change in radiation level:

Radiation level is R.

Rate of change indicates that the radiation level R varies in function of time t, which mathematically means that we have:

(dR)/(dt)

After the reactor is shut down, the radiation from the nitrogen-17 decreases in such a way that the rate of change in the radiation level is directly proportional to the radiation level.

Rate of change is k. Decreases means that k is negative. Proportional to the radiation level of R means that -k multiplies R. So the differential equation is:

(dR)/(dt) = -kR

Let n = 5.What is the value of the expression 9n2−2−n?

Enter your answer in the box.

Answers

Answer:

9 (5) 2 - 2 - 5 = 83