There is no solution to this set that works for both equations. If you multiply the top equation by 2 and then add them together, the x and y numbers will cancel. This leaves you with 0 =1010, which is never true.
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
No, this would not be a biased question unless the people asked were all Thai people or all Chinese people. Then the information would be skewed because naturally, Chinese people would favor Chinese food and same for Thai.
Answer:
Both, you and your friend, are correct.
Step-by-step explanation:
5 P 5 = 5!
A shortcut I learned is that in the permutation equation nPn when n is the same on both sides, it is equal to if you used factorial, n!.
Answer:
the last one
Step-by-step explanation: