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:
-1/2
Step-by-step explanation:
Answer: 68
Step-by-step explanation:
range=47 lowest score = 21 let highest score =x
Range=highest score - lowest score
47 = x - 21
x = 47 + 21
x = 68
Therefore the highest score is 68
3x-2 if x is less an or greater than 1, will be a negative y value.
-2x+3 when x is greater than 1 will also be a negative y value.
The graph would be the first one ( an upside down V)
Answer:
9 =6x
Step-by-step explanation:
We know this is the answer because the -4x was cancelled out left to the equal sign, and 2x has now become 6x after adding 4x.