Complete question :
The 100m dah times in the girl's track meet were normally distributed with a mean of 13 seconds and a standard deviation of 0.3 seconds.
Lana finished the race in 13.2 seconds . If 84 other girls ran in the event, approximately how many runners did she beat?
Answer:
21 runners
Step-by-step explanation:
Mean, μ = 13 seconds
Standard deviation, σ = 0.3
Lana's race time = 13.2
We find the proportion of runners who had race time above 13.2 ;
Proportion of who had race tune above 13.2
P(x > 13.2)
Obtain the Zscore
Zscore = (x - μ) / σ
Z = (13.2 - 13) / 0.3
Zscore = 0.2 / 0.3 = 0.6667
P(Z > 0.6667) = 0.25239 (Z probability calculator)
This is about 0.25239 * 100 = 25.24% = 25% (nearest percent)
Hence, Number of runners Lana beat = 25% of total runners ;
0.25 * 84 = 21
Hence, Lana beat about 21 runners
part A)
![\bf \begin{array}{|c|cccccc|ll} \cline{1-7} x&8&27&64&125&&x\\ \cline{1-7} y&\stackrel{\sqrt[3]{8}}{2}&\stackrel{\sqrt[3]{27}}{3}&\stackrel{\sqrt[3]{64}}{4}&\stackrel{\sqrt[3]{125}}{5}&&\sqrt[3]{x} \\ \cline{1-7} \end{array}~\hspace{10em}y = \sqrt[3]{x}](https://tex.z-dn.net/?f=%5Cbf%20%5Cbegin%7Barray%7D%7B%7Cc%7Ccccccc%7Cll%7D%20%5Ccline%7B1-7%7D%20x%268%2627%2664%26125%26%26x%5C%5C%20%5Ccline%7B1-7%7D%20y%26%5Cstackrel%7B%5Csqrt%5B3%5D%7B8%7D%7D%7B2%7D%26%5Cstackrel%7B%5Csqrt%5B3%5D%7B27%7D%7D%7B3%7D%26%5Cstackrel%7B%5Csqrt%5B3%5D%7B64%7D%7D%7B4%7D%26%5Cstackrel%7B%5Csqrt%5B3%5D%7B125%7D%7D%7B5%7D%26%26%5Csqrt%5B3%5D%7Bx%7D%20%5C%5C%20%5Ccline%7B1-7%7D%20%5Cend%7Barray%7D~%5Chspace%7B10em%7Dy%20%3D%20%5Csqrt%5B3%5D%7Bx%7D)
part B)
f(x) = 10 + 20x
so if you rent the bike for a few hours that is
1 hr.............................10 + 20(1)
2 hrs..........................10 + 20(2)
3 hrs..........................10 + 20(3)
so the cost is really some fixed 10 + 20 bucks per hour, usually the 10 bucks is for some paperwork fee, so you go to the bike shop, and they'd say, ok is 10 bucks to set up a membership and 20 bucks per hour for using it, thereabouts.
f(100) = 10 + 20(100) => f(100) = 2010.
f(100), the cost of renting the bike for 100 hours.
Y
=
−
2
x
+
5
y
=
-
2
x
+
5
Use the slope-intercept form to find the slope and y-intercept.
Tap for more steps...
Slope:
−
2
-
2
y-intercept:
(
0
,
5
)
(
0
,
5
)
Any line can be graphed using two points. Select two
x
x
values, and plug them into the equation to find the corresponding
y
y
values.
Tap for more steps...
x
y
0
5
5
2
0
Stop asking questons we are pretty much telling you the answer figure it out your self
Answer:
3
Step-by-step explanation:
8.4 ÷ 3 = 2.8
(Hopefully this answers your question)
