Calculation I. Thénominal w eight of a chocolate bar is 50.0±2.5 g . Measuring s

Question

Calculation I. Thénominal w eight of a chocolate bar is 50.0±2.5 g . Measuring several chocolate bars, it was found that the average (expected) weight is 49.5g and the variance of the weight is 1.3g What percentage of these chocolate bars has a weight less than 50.0 g? 2. The nitrate content of a natural water sample was measured with 7 repetitions. The results are: 70.6, 68.5, 73.8, 65.4, 77.2, 69.1, 75.6 (mg/). a Give a limit that the variance of the meas rement does not exceed with 95% prob b) Can we ability. prove based on the data, that the nitrate content of the water sample is lower than 75.0 mg/l? (At = 5% level.) ? In o laboratory a new snectrophotometer was installed. The personnel wanted to check

Explanation / Answer

We can say that data is normally distributed with a mean of 49.5. and variance of 1.3

we know that we can calculate the standard deviation from the variance by taking square root of 1.3 which is 1.140

z value at 50g

Z = (X - ) /
Z = (50 - 49.5) / 1.14

Z = 0.4386

from z score table p(x<=50.0 g) = 0.6695 (0.67 approx)

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.