II Unknown to a quality assurance technician the tensile str

II. Unknown to a quality assurance technician, the tensile strengths (in pounds per square inch. psi XR04074. Because a bolt must be broken to measure its strength, the testing processis is destructive. The technician plans to collect a simple random sample of 20 bolts, then measure how much tension each one withstands before it breaks. Generate the simple random sample and compute its mean breaking strength. Assuming that the bolt manufacturer has advertised that, on average, such bolts will withstand 10,000 psi, refer to your sample result in commenting on the manufacturer\'s claim. (We will discuss the List the snadents List i) forall 500 heavy-duty construction bolts in a recent shipment are as listed in file use of sample data in evaluating claims in much greater detail in Chapter 10, Hypothesis Testing.) A BCD tensile 10102 310083 10046 10049 10045 710083 tensile Slo 04074 Mean Standard E 3.046009 Median Mode Standard C 68.11083 10098.2 810222 10206 10098.5 10073 10150 1010150 10254 10026 Sample Va 4639.085 Kurtosis 13 10090 10024 15 10021 Kurtosis 0.127905 Skewness -0.01322 Range Minimum Maximum 389 9886 10275 : 50490991 500 1610012 17 10184 Sum Count 1 | 10184

Solution

First create hypotheses as

H0: mu >= 10000 psi

Ha: mu < 10000 psi

(one tailed test)

x bar = 10098.2

Std error = 3.046

x bar - mu = 98.2

As n =500, normal test can be used

Z = 98.2/3.046 = 32.24

p value is 1

Since p >0.05 accept null hypothesis.

the wire can withstand upto 10000