Math375: Introduction to Statistics
Practice Problems for Exam #2
1. P336. 7. The capacities ( in ampere-hours) were measured for a sample of 120 batteries.
The average was 178 and the standard deviation was 14.
x = 178, s = 14, n = 120
(a) Find a 95% con
Math375: Introduction to Statistics
Practice Problems for Exam #2
1. P336. 7. The capacities ( in ampere-hours) were measured for a sample of 120 batteries.
The average was 178 and the standard deviation was 14.
(a) Find a 95% condence interval for the me
Round all intermediate steps to six decimal places if necessary.
As part of the qualitycontrol program for a catalyst manufacturing line, the raw materials
(alumina and a binder) are tested for purity. The process requires that the purity of the
alumina b
Suppose you have a sample of six spacer collars, whose thicknesses (in mm) are 39.011, 38.994,
39.014, 39.007, 39.016, and 39.008. We denoted the population mean thickness by and tested
the hypotheses
H 0 : = 39.00 versus H 1 : 39.00
Now assume that these
Math375: Introduction to Statistics
Practice Problems for Exam #2
1. P336. 7. The capacities ( in ampere-hours) were measured for a sample of 120 batteries.
The average was 178 and the standard deviation was 14.
x = 178, s = 14, n = 120
(a) Find a 95% con
Math375: Introduction to Statistics
Practice Problems for Final Exam
1. P522. 9. Tire pressure (in kPa) was measured for the right and left front tires on a
sample of 10 automobiles. Assume that the tire pressures follow a bivariate normal
distributions.
Formulas for Final Exam
X Bin(n, p), then the pmf is
P (X = x) =
n x
p (1 p)nx ,
x
x = 0, 1, ., n
= np; 2 = np(1 p)
X P oisson(), then the pmf is
P (X = x) =
e x
,
x!
x = 0, 1, 2, .
= ; 2 =
X Exponential(), then the pdf is
f (x) = ex ,
1
= ; 2 =
x>