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:
Nikolai Lobachevsky and Bernhard Riemann
Step-by-step explanation:
Nikolai Lobachevsky (A russian mathematician born in 1792) and Bernhard Riemann (A german mathematician born in 1826) are the mathematicians that helped to discover alternatives to euclidean geometry in the nineteenth century.
yes.
this is division. 36 divided by 12 is 3. 63 divided by 21 is 3.
Answer:
You have to use the Pythagorean Theorem to find the other side, which will be your base in the Area formula (A=1/2bh). So the Pythagorean theorem would be 36^2 + b^2 = 60^2. This gives you 48 in for your base/missing side length. Then, you plug it into the area formula. So, A=1/2(48) (36). This gives you 864 in^2 for the area of your triangle.
-2/15=13/15
Step-by-step explanation:
2/3-4/5=13/15
2/15=13/15
