Question: Swimming's 4 x 100 medley relay consists of teams of 4 swimmers, each swimming 100 meters in a diff. style (backstroke, breaststroke, butterfly, freestyle). From past experience, the 4 swimmers on team canada know that their race times follow normal distributions with the following means and standard deviations (in seconds). Times for all swimmers are known to be independent.
here's the table:
Swimmer 1 (backstroke): mean = 53.2 , std=0.8
2 (breaststroke): mean= 61.3 , std=0.9
3 (butterfly): mean=51., std = 0.7
4 (freestyle): mean=48.0 , std=0.6
A) in any given race, what is the probability that swimmer 1 has a time less than 54.5 seconds?
B) according to the 68-95-99.7% rule, the central 95% of the distribution times for swimmer falls between what two values? Edit
Answer: A. Need to find P(x<54.5)=?
Test statistic, z= (x - mean)/sd = (x-53.2)/0.8
if x= 54.5 , then z= (54.5-53.2)/0.8=1.625
TutorTeddy.com & Boston Predictive Analytics
[ Email your Statistics or Math problems to email@example.com (camera phone photos are OK) ]
Boston Office (Near MIT/Kendall 'T'):
Cambridge Innovation Center,
One Broadway, 14th Floor,
Cambridge, MA 02142,
Dallas Office (Near Galleria):
15950 Dallas Parkway,
Dallas, TX 75248,