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:
centimeters
Step-by-step explanation:
The numerator of the conversion factor always has the "to" units. The denominator has the "from" units. That way, when you multiply, the "from" units cancel:
(xx <em>from</em>) · (yy <em>to</em>)/(zz <em>from</em>) = xx·yy/zz · (<em>from/from</em>) · <em>to</em> = xx·yy/zz · <em>to</em>
Here, you want to convert to centimeters, so centimeters will be the units in the numerator.
10 in · (2.54 cm)/(1 in) = 25.4 cm
_____
The conversion factor is always "1". That is, the numerator and denominator are always <u>equal</u> in value. Here, 2.54 cm = 1 in, so (2.54 cm)/(1 in) = 1. You can multiply by 1 anytime you like. For units conversion, it only has the effect of changing the units.
Answer:
1. 0.33 2. 0.16 3. o.11
Step-by-step explanation:
Your answer will be 150 percent
