Fred, a local mechanic, gathered the following data regarding the price, in doll

Question

Fred, a local mechanic, gathered the following data regarding the price, in dollars, of an oil and filter change at twelve competing service stations: 32.95 24.95 26.95 28.95 18.95 28.95 30.95 22.95 24.95 26.95 29.95 28.95 Round results to the nearest tenth. The maximum value of a distribution is 36.3 and the minimum value is 3.3. Estimate the standard deviation with the Range Rule of Thumb. At one college, GPA's are normally distributed with a mean of 2.7 and a standard deviation of 0.4. What percentage of students at the college have a GPA between 2.3 and 3.1? Consider a score to be unusual if its z-score is less than -2.00 or greater than 2.00. Round the z-score to the nearest tenth if necessary. A body temperature of 99.7 degree F given that human body temperatures have a mean of 98.20 degree F and a standard deviation of 0.62 degree

Explanation / Answer

7)

Range = Max - Min = 14

8)

Range = 36.3 - 3.3 = 33

standard deviation, s = R/4 = 33/4 = 8.25

9)
mean = 2.7
std. dev. = 0.4

2.7 - 0.4 = 2.3
2.8 + 0.4 = 3.1
This means we need to find the percentage of students with 1-sigma level.

As per empirical rule, 67% of population lies within 1-sigma level.

Hence 67% of students at the college have a GPA between 2.3 nd 3.1.

10)

Here we need to find the z-score corresponding to body temp of 99 degree F.

As per central limit theorem,
z = (99 - 98.2)/0.62 = 1.2903

This z-score value is not unusaual.

Min 18.95 Max 32.95

Related Questions

Navigate

• Browse (All)
• Browse F
• Subjects

---

---

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