MidtermReview4
coefficient
of his lineof bestfit to be
1.
the correlation
Stananalyzesa set of dataanddetermine
the
coefficient
of herlineto
| -.42. Juliannanalyzes
anothersetof dataanddetermine correlation
be r=- .8 1 .
lr f ctort{ {a'I
is true?
Basedon theseresults.whichstatement
1)
2)
o
4)
linefitshersbecausehiscorrelation
Stan'slinefitshisdatabetterthanJuliann's
is closestto zero.
coefficient
linefitshersbecausehiscorrelation
Stan'slinefitshisdatabetterthanJuliann's
is positive.
coefficient
linefitsherdatabetterthanStan'slinefitshis becausehercorrelation
Juliann's
is closestto t1.
coefficient
linefitsherdatabetterthanStan'slinefitshis becausehercorrelation
Juliann's
coefficient
is negative.
its costsfromits revenue.lf the revenue
2.
The profitof a businessis determineby subtracting
by 2x2-3x +2,
by 4x2-5x+2 anditscostcanbe represented
of a business
canbe represented
whichexpression
represents
its profit?
2)
3)
- 2 x 2 +2 x
- 2 x 2 -8 x+4
4)
2 x 2 -8 x+4
+ 7xA-5x r$
Q -axa@xGA
Jx'-&,r
Ellawantsto purchase
has$145,andearnsan allowance
of
3.
a bicyclefor $265.Shecurrently
per
Which
number
must
she
week.
of weekswElla
saveuntil
equation
canbe usedto findthe
$5
the bicycle?
can purchase
1)
2)
< _9)
4)
1 4 5x+5 = 2 6 5
2 6 5+ 5 x:1 4 5
r lLlb,
.-t-=2TEfu.A
5 ?n, cu'eek
5x
5x + 1 4 5 = 2 6 5
'lD Sfclf
+
tq5
t
z
,.L5
2 6 5x+5 = 1 4 5
4.
Members
of an onlinemovieclubpaya $120membership
fee,andcanpurchase
moviesfor
per
purchase
per
movie.Non-members
moviesfromthesameclubfor $15
movie.
can
$5
purchase
non-members
andmembers
the samenumberof moviesandpay
lWtrqlis thecostlwtren
the sameamount?
1)
2)
3
4)
6
12
150
180
| 5 ,n
-5rn
- 5rn
,a o
-
IU
,'-\
tA
lc
=fn
: tS(i)
5 (ra)rtao
bo+teoI go
l7o : lyo
Fourstudents
5.
analyzedifferent
dataanddetermine
theequation
of a lineof bestfit. Their
resultsareshownin thetablebelow:
Student
Equation
Correlation
Coefficient
Austin
Y =-8 .6 1 x+9 9 .2 3
r= -0.83
Brittany
y :3.8x +2.45
r= 0.76
Cali
Y = -0.04x+112.32
r= -0.72
Derrick
y=0 .8 1 -1 .3 4
1.l,I
l tl ol os es
r = 0.81
Whoseequation
fitstheirdatabest?
2)
3)
4)
6.
Austi
Brittany
Cali
Derrick
Thetablebelowshowsthe population
of NewYorkCityin 1O-year
intervals.
Year
1970
1980
1990
2000
2010
Population 7,894,862 7,071,639 7,322,564 8,008,288 8,175,133
Whichof thefollowingstatements
i{ry/true?
3)
Thepopulation
of NewYorkCitydecreased
by approximately
82,000peopleperVear(\
'729'1g1rS'
=
FAJAa7O-I|G'?
f23,2fi/tc
between1970and 1980.
The population
of NewYorkCitydecreased
by approximately
28p0peoplepetyeay;A
-g/
-J7./dg
between1970and 1990. A 3,le5L7 '/811,/8()=
The population
of NewYorkC_ity
increased
by approximately
3700peopleperyear ./-7:\
4)
The population
of NewYorkCityincreased
by approximately
7000peopleperyeal
1)
between
1e70
and2000. Soog)7r - 7'gqiVrof= /Pq)6/Ji
between
1e70and2010. F ) Sr j j'
='ffi
7'tq('16 L = J FOJI)7+)=lf,t
aU
@
7.
Whenbabysitting,
Nicolechargesan hourlyfeeandan additional
chargefor gasfor hercar.
:
SheusestheequationF 6h + 5 to determine
howmuchsheearnsfor babysitting.
They-intercept
of thegraphof thisequation
represents
1)
the numberof hoursNicolebabysits
the hourlyfee Nicolecha
e for qasfor hercai
thetotalNicoleearnsfrom
F = Uh r5
..k
v
S Iugz
rl-tnlarePt
8.
Whichdescription
bestmatchesthegraphbelow?
v
t
0/
E1
Flra
t)?46
o
2)
3)
4)
9.
f imc {e)
A personwalkstowardsa motionsensor,stopsfor 2 seconds,and walksaway
fromthe sensor.
A personwalksbackward,
stopsfor 2 seconds,andwalksforward.
A personwalksdownhill,
stopson levelgroundfor 2 seconds,
andwalksuphill.
person
walksawayfroma motionsensor,stopsfor 2 seconds,andwalkstowards
A
the sensor.
When3x2+ 6x - 9 is subtracted
from 8x2+ 6x - 4, the resultis
;-\
gx t t-6x-4 6^irL;-?)
1)
- 5 x 2 -5
2)
- 5 x 2 +1 2 x -5
5 r ^ +3
5x'+
4)
10.
Emmahassaved$195,andwantsto buyan iPodthatcosts$02S.Sheearnsan allowance
of
per
Which
week.
equation
to
can
be
used
determine
the
number
vy
Emma
of
weeks
must
$5
saveuntilshecanpurchase
the iPod?
1)
/------
@
3)
4)
11.
5 x 2-1 2 x + 5
t- non\
C= Srtnuseek'
31b= 5x + n lJ
5 + 1 9 5 x =3 7 5
5+375x = 195
5 x +3 7 5 :1 9 5
S.t-ve?*
Th e e q u a ti on
F:5200-250y repr e s e n t s t h e n u m b ef is
r ohf in a la k e F
, , a f t e r y y e a r s.
Explainthe real-world
meaningof the 5200andthe -250.,
\
(tos) ioc &th ever1fear
Jaco AsA(,^+L lutre lo -slt-rt\
/ \-'
\
+
Givea real-world
explanation
as to whythe5200is positive
andthe 250is negative.
12.
l l P = 3 x 2 - 5 x+4 ,
Q=-x2 +3 x, and R:2x2- 7x+ l,expr ess
- R+2P*3Q asat r i nom i al .
-K r ) f -3 4
- (e^a-7r t-t)r J,(zP- 5xn) -3 (-x*! 3^)
@m4@m'r@m
13.
7x *- / ) x *7
Thedatabelowrepresents
the quartergradefor a classol 20 students.
-A tts u e r
7 7, 84,64,17,74, 90,27,7 6 , 8 95, 1, 7 3 , 4 4 ,6 4 , 7 8 , 5 98, 4 ,6 8 ,6 8 ,5 0 ,5 8
range. Q I '= 7 7, {
Determine
andstatethevalueoftheinterquartile
Ot - 41 ' r e(
Q r "t r , , E / vlay?o
Determine
if anyoutliers
inthedata.
u!"v'e
exist
-^'-'d;
:''3i'*{
/, j '/ raK
7A('
e3'
l'{ledtu* bg
*t'g
a-\ i9zr
-/:s
-- o:'
i s'an,e
,J;,t{#%;,,€3ti
r
^r"f:;;,,ii;{;ffi^
14.
i/lrn 11
/Yl<"i
.r,-h'
7,
tJ:
7,
y
^
f
,fl
t>
if
/ess
tAa-a
Q:
-?? JA,
A classdoesa bungee-jumping
witha Barbiedoll. Thetablebelowshowsthe
experiment
y,
in
with
rubber
stretch
centimeters, a
bandchainmadeof x rubberbands.
Numberof
rubberbands(x)
3
7
I
11
14
16
20
cm of stretch(y)
13
24
30
34
45
51
70
Determine
the equation
of the lineof bestfit. Roundallvaluesto the nearesthundredth.
[)z
lg=
3,265t'l,
c.8tb5E,
y = 3,r7x * o,g3
/
Useyourequation
to predictthestretch,
in centimeters,
of a bungeejumpconsisting
of 26
rubberOands./X)
(au)/-o,
=
/
3,et
{3
Y :, =75tcY:-o,{s
C rn .o F s fr<-fc/t
trs ,9 j
)k LLse\NwLI-,LWh en'l+r
lrfienu 4 6+ar5), I (slv-f (ilc),
s ; {Ae'u
3 (trn(ar /ejranzm)
\
15.
PV charges$40
fee,whileCrossFit
MuscleGymcosts$30permonthwitha $120membership
permonthwithno initiation
fee.
- onefor thecostC of m monthsof membership
at eachgym.
Write2 equations
cv^, SDrn + I aO
CostatMuscle
Pv: 4 C rr)
CostatcrossFit
/ n=+
b-tto
on the axesbelow.
Grapheachequation
/ 0 =W b =O
I
C*"frt UUL
D IO
6Vm
[tr.tsc/e6
''],L',
1lt20
. ilt
, - i' n
rrl
i
1l iuo
5{ ;oo
fi:i
It.
b I xvo
lt
,.r.- -r.-"--l -l -"."-
.--,*;.
I
O
8 | 3to
.ii
..,..-.-:..,.. .. i,,., .,,!^--
-
,i'i
3oo
r i;i
'' - i - - ' r " - - t- - - '{
';
i
7l ?rD
-i
"-- r
-'
cllsuo
loI voo
u I qvD
D|'wa
rl f 5ao
I
l. -l
10
- - - .1- ..,- .- .i ., - .L- - ,...1 - .- ;.,- - - - ,.1..,.- - :,
12
14
16
18
i
20
Months
the numberof monthsfor whichjoiningCrossFitPV is a betterdeal.
Usethegraphto determine
n n1c n * h s