Some registered nurses earn $141.75 for working 4.5 hours. What is the hourly rate?

A GE lightbulb is supposed to last for 1,200 hours. In fact, light bulbs of this type last only 1,185 hours with a standard devi

dybincka [34]

This can be solved using the formula for t test which is = x - mu over standard deviation divided by the square root of the number of samples. In this case, it is 1185 - 1200 over 70 divided by square root of 100 which give us a value of 2.14 which is equal to .9839 in area. Only rarely, just over one time in a hundred tries of 100 light bulbs, would the average life exceed 1200 hours.

7 0

2 years ago

Data on the oxide thickness of semiconductor wafers are as follows: 425, 431, 416, 419, 421, 436, 418, 410, 431, 433, 423, 426,

DanielleElmas [232]

Answer:

423

Step-by-step explanation:

The sample mean is a point estimate of the population mean.

Therefore a point estimate of the mean oxide thickness for all wafers in the population is the mean of the sample data on the oxide thickness of semiconductor wafers.

To calculate the sample mean, we sum all the sample data and divide by the sample size which is 24. We get 423.33 ≈423

7 0

2 years ago

Bonita has a standard of 2 hours of labor per unit, at $12 per hour. In producing 2600 units, Bonita used 5050 hours of labor at

Eduardwww [97]

Answer:

1800

Step-by-step explanation:

Labor quantity variance= Actual quantity ×standard price - standard quantity ×standard price

Standard quantity=2×2600=5200

Labor quantity variance

5050×12-5200×12=1800

3 0

2 years ago

A high school drama teacher organizes a musical production. He wants to record the number of students involved in each part of t

crimeas [40]

I’m can’t freakin stay up I need to sleep and I need to get 4 papers done for my portfolio I can’t help but I wish you luck

5 0

2 years ago

The quality control manager at a light bulb factory needs to estimate the mean life of a batch (population) of light bulbs. We a

Nadusha1986 [10]

Answer:

a)95% confidence intervals for the population mean of light bulbs in this batch

(325.5 ,374.5)

b)

The calculated value Z = 4 > 1.96 at 0.05 level of significance

Null hypothesis is rejected

The manufacturer has not right to take the average life of the light bulbs is 400 hours.

Step-by-step explanation:

Given sample size n = 64

Given mean of the sample x⁻ = 350

Standard deviation of the Population σ = 100 hours

The tabulated value Z₀.₉₅ = 1.96

95% confidence intervals for the population mean of light bulbs in this batch

$(x^{-} - Z_{\frac{\alpha }{2} } \frac{S.D}{\sqrt{n} } , x^{-} + Z_{\frac{\alpha }{2} }\frac{S.D}{\sqrt{n} } )$

$(350 - 1.96\frac{100}{\sqrt{64} } , 350 + 1.96\frac{100}{\sqrt{64} } )$

$(350 -24.5, 350 +24.5)$

(325.5 ,374.5)

b)

Explanation:-

Given mean of the Population μ = 400

Given sample size n = 64

Given mean of the sample x⁻ = 350

Standard deviation of the Population σ = 100 hours

Null hypothesis : H₀:The manufacturer has right to take the average life of the light bulbs is 400 hours.

μ = 400

Alternative Hypothesis: H₁: μ ≠400

The test statistic

$Z = \frac{x^{-}-mean }{\frac{S.D}{\sqrt{n} } }$

$Z = \frac{350 -400}{\frac{100}{\sqrt{64} } }$

|Z| = |-4|

The tabulated value Z₀.₉₅ = 1.96

The calculated value Z = 4 > 1.96 at 0.05 level of significance

Null hypothesis is rejected.

Conclusion:-

The manufacturer has not right to take the average life of the light bulbs is 400 hours.

5 0

2 years ago