Solutions to Exam #1, Version B and D
Question
No. on
Ver
B
Solutions Version
B
Version D
Solutions
Quest and
Ans
1 The T critical value can be found from the table, which is 2.82. B Q3 – D
2 Since P(0.4152) > α (0.01), FTR E Q4 – B
3 Look at the P(two-tail) value in the table since it compares the
difference between the two means.
D Q1 – A
4 P(0.0071) < α (0.05), Reject Ho. A Q2 – C
5 It wanted to test if there is a difference between proportions from
two offices
A Q8 – C
6 P=(x1 + x2)/(n1 + n2) = (44+39)/(270 + 320)=0.1407
P1 = 44/270 = 0.1630, P2 = 39/320 = 0.1219
____________________
|Z|= (P1-P2)/√[P(1-P)]/n1 + [P(1-P)]/n2 = 0.0411/0.0287 = 1.4321,
since the Zα/2 = 2.575
So, FTR since |Z|< Zα/2.
A Q9 – C
7 Lower limit: (P1-P2)- Zα/2 *
____________________________
√[P1(1-P1)]/(n1-1) + [P2(1-P2)]/(n2-1) = -0.0158, the red part of the
formula is 0.0582. So the upper limit: (P1-P2)+0.0569 =
0.0411+0.0569=0.098
E Q10 – B
8 The question wanted to test if the proportion has increased,
therefore Ha: p > 0.21, Ho: p ≤0.21
D Q5 – A
9 Z= [(78/350) – 0.21]/ √[0.21*(1-0.21)]/350 = 0.5905 B Q6 – D
10 2.43 corresponds to 0.4896, 05-0.4925 = 0.0104 A Q7 – C
11 Ha: not all means are equal A Q14 – C
12 Dollar amount of sales B Q15 – D
13 F =
MS(factor)/MS(error)=(116.41/3)/(356.55/20)=38.80/17.8275=2.
176
E Q16 – C
14 Since F<Fcrit (3.0984), FTR. D Q17 – B
15 Sum of square = 3*6479.76 = 19439.28 D Q11 – B
16 MS(error) = 7475.475/27 = 276.869, F=326.581/276.869=1.179 D Q12 – B
17 Since P (9.29E-08) < α(0.05), reject Ho E Q13 – A
