Question

1. A section of the printout for a multiple regression model attempting to predict results in an RMIT maths subject is shown below. The variables ATAR score, MathsReady test score, attendance at SLC Drop-in and hours of study per week were considered. The 95% confidence interval for the intercept is [1.24, 18.22] or 1.24 - 18.22. A variable is considered a significant predictor if the 95% confidence interval does not contain zero.

$21_qstn_5.png$

Which of the variables ‘ATAR score’, ‘MathsReady test score’, ‘attendance at SLC Drop-in’ and ‘hours of study per week’ were significant predictors?

A. ‘MathsReady test score’ and ‘hours of study per week’

B.‘ATAR score’ and ‘hours of study per week’

C.‘ATAR score’ and ‘attendance at SLC Drop-in’

D.‘MathsReady test score’ and ‘hours of study per week’

E.Only ‘ATAR score’

2. The bell-shaped curve shown below is symmetrical with an equal area in each of the shaded tail regions.

$19_qstn_1.png$

If 10% of the total area under the curve is in one tail what percentage of the total area is in the central region?

A.20%

B.40%

C.50%

D.80%

E.90%

3.

The area of a region to the left of a particular value of z is known to be greater than 0.64. Then z could NOT be:

A. 0.61

B. 0.56

C. 0.73

D .0.32

E. 0.41

4. Looking at diagram 3, The area of a region to the left of a particular value of z is known to be less than 0.75. Then z could NOT be:

A.0.61

B.0.56

C.0.41

D.0.52

E.0.73

5.If the formula $LaTeX: z=\frac{x+\mu}{\sigma}$ z=x+μσ is rearranged to make $LaTeX: \mu$μ the subject, then:

A.$LaTeX: \mu=z\sigma-x$μ=zσ−x

B.$LaTeX: \mu=x-z\sigma$μ=x−zσ

C.$LaTeX: \mu=\left(z-x\right)\sigma$μ=(z−x)σ

D.$LaTeX: \mu=\left(z+x\right)\sigma$μ=(z+x)σ

E.$LaTeX: \mu=x+z\sigma$

6.If 200 ± 5 × 20 → (100, 300) then 25 ± 1.5 × 10 →

A.(20, 30)

B.(235, 265)

C.(-125, 175)

D.(10, 40)

E.None of these

7.Which of the following is NOT a correct statement?

A.Less than half of the data is between 43 and 60

B.The mean, mode, and median of the data are all 52

C.The range of the data is more than 30

D.Half of the data is below 52

E.Most of the data falls within the range 40 - 64

8.Which of the following statements CANNOT be inferred from the graph?

A.An elevation of 1500m is associated with a mean annual temperature of approximately 8 degrees

B.Mean temperature tends to decrease with elevation

C.The mean annual temperature does not rise above 20 degrees at any elevation

D.The data is approximately linear

E.For every increase in elevation of 500m the mean annual temperature changes by approximately 20 degrees

9.What percentage of students who passed are female?

A.80%

B.100%

C.50%

D.40%

E.60%

10.Which of the following is the correct expansion of ∑i=14(i−2)?

A.1 + 2 + 3 + 4 - 2

B.1 - 2 + 2 - 2 + 3 - 2 + 4 - 2

C.1 + 4 - 2

D.1 - 2 + 4 - 2

E.1 × 2 × 3 × 4 - 2

The table below can be used to find the area of the shaded region to the left of a given value of z. For example, the highlighted entry shows that the area to the left of 0.72 is 0.7642 Z (second decimal place) 0.00 0.0 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.0 0.5000 0.5040 0.5080 0.5120 0.5160 0.5199 0.5239 0.5279 0.5319 0.5359 0.1 0.5398 0.5438 0.5478 0.5517 0.5557 0.5596 0.5636 0.5675 0.5714 0.5753 0.2 0.5793 0.5832 0.5871 0.5910 0.5948 0.5987 0.6026 0.6064 0.6103 0.6141 0.3 0.6179 0.6217 0.6255 0.6293 0.6331 0.6368 0.6406 0.6443 0.6480 0.6517 Z (first decimal place) 0.4 0.6554 0.6591 0.6628 0.6664 0.6700 0.6736 0.6772 0.6808 0.6844 0.6879 0.5 0.6915 0.6950 0.6985 0.7019 0.7054 0.7088 0.7123 0.7157 0.7190 0.7224 0.6 0.7257 0.7291 0.7324 0.7357 0.7389 0.7422 0.7454 0.7486 0.7517 0.7549 0.7 0.7580 0.761 0.7642 0.7673 0.7704 0.7734 0.7764 0.7794 0.7823 0.7852 0.8 0.7881 0.7910 0.7939 0.7967 0.7995 0.8023 0.8051 0.8078 0.8106 0.8133 0.9 0.8159 0.8186 0.8212 0.8238 0.8264 0.8289 0.8315 0.8340 0.8365 0.8389 0 0.8413 0.8438 0.8461 0.8485 0.8508 0.8531 0.8554 0.8577 0.8599 0.8621 34 40 46 52 58 64 70 25 20 ト15 0 0 500 1000 1500 2000 2500 Elevation (m) Pass Fail Male40 20 60 Female 40 040 8020 100 Each term looks like this Last value of A sum of terms First value of This value wi11 change with each ASY This will remain constant with each term Σ4=1 (i -2)

Answer 1

5.If the formula $LaTeX: z=\frac{x+\mu}{\sigma}$ z=x+μσ is rearranged to make $LaTeX: \mu$μ the subject, then:

μ=zσ-x

μ=zσ−x

MARK OPTION A

Solution6:

25 ± 1.5 × 10

25-1.5*10,25+1.5*10

10,40

MARK OPTION D

D.(10, 40)

10.Which of the following is the correct expansion of

Σ4=1 (i -2)

=sigma means sum

=1-2+2-2+3-2+4-2

MARK OPTION B

Solution3:

Use R software

RStudio ile Edit Code Vew Plots SessionBuild Debug Pr ools Help 1の1日: i source on Save 1 ibrary(tigerstats 2 pnormKK (bound-O, 32 , region-"below" ,mean-D , s d-1,grהph-TRUE) pormGC (bound-0.56, region-"below" ,mea-0,sd-1,graph-TRUE) 11 0.7122603 pnormGC(baund-D.73, region-"helaw",mean-0,-1,graph-TRUE) [1] 0.767 3049 s pnormGC (bound-0. 32,region-"below" ,mean-0,sd-1,graph-TRUE) 1] 0.6255158 > pnormGC (bound-0.41,region-"below" ,mean-0,sd-1,graph-TRUE) 1] 0.659097 pormGbord-0.41,regio-"below" , meari-0,sd-1,graph-TRUE) [1 | 0 . 63909/ pnormond-.3,region-"helaw",mean-0,-,graph-TRUF) 1] 0.6255158 0.61 Files Plots Packages Help Viewer Normal Curve, mean 0 , SD Shaded Area 0.6255 1 3:1 @Р Leve0 ; R Scnpt Global Enirormen num [1:10, 11 66.1 84 56.1 63.5 79.2 rN Values data num 11:401 18 74 28 46 31 48 51 35 52 40 num [1:15] 1.57 1.63 1.67 1.34 1.52 1.34 1.56 1.49 1.34 1.55 1000 num 1:75] 55.3 55.3 55.3 55.9 55.9 56.1 56.1 56.1 56.1 56.1 noisclevcl task temperature int [1:1000] 1 41268 76 39 num [1:10] 100 110 120 130 140 150 160 170 180 190 num 1:41 13 5 7 num 11:10] 44 85 21 38 74 62 68 83 90 79 num [1:5] 4 32.3 26.2 16.2 13.9 num [1:10] 60,2 64.3 72.4 86,3 80.3 x old ield 8:41 PM Type here to search

Normal Curve, mean 0, SD 1 Shaded Area 0.6255 寸 02 0

Rcode:

library(tigerstats)
pnormGC(bound=0.41,region="below",mean=0,sd=1,graph=TRUE)

ANSWER:

0.32