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
Answer:
12.5%
Step-by-step explanation:
$4.50-$4/$4 x 100%
0.5/4x100%
50/4= 25/2 = 12.5%
Answer:
C
Step-by-step explanation:
240m= 4h
120km
V= 120/4 = 30 km/h
I hope this helps, have a good day
Answer:
I'm not too sure but I think it's 37.7
Step-by-step explanation:
radius of the base times height is supposed to equal the volume but I'm bad at geometry
Answer:
I got x=5/2; y=0 lmk if it works
Step-by-step explanation: