statistics
posted by Ashley .
The average scuba diver can stay under water for 42 minutes with a standard deviation of 8 minutes.(show graph)
B. what is the probabilty that a diver stays under for the less than 53 minutes?
c.what is the probabilty that a diver stays under between 25 and 50?
d. what is the probabilty that a diver stays under for more than 52 mintues?
e.find the cutoff number for the middle 50% of the time a diver stays down?
f.find the top 15% of time the diver stays down?
g. find the bottom 20%of the time a diver stays down?

Z = (scoremean)/SD
Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion related to the Z scores.
For eg reverse the process in the table and insert the Z value in the equation above.
Respond to this Question
Similar Questions

Advanced Functions  Grade 12
The maximum time, T, in minutes, a scuba diver can rise without stopping for decompression on the way to the surface is modeled by the equation T (d) = 525/d10 , d > 10, where d is the depth of the dive in metres. a) sketch a graph … 
statistics
The average scuba diver can stay under water for 42 minutes with a standard deviation of 8 minutes, what is the probability that a diver stays under for more than 36 minutes 
statistics
The average scuba diver can stay under water for 42 minutes with a standard deviation of 8 minutes.(show graph) B. what is the probabilty that a diver stays under for the less than 53 minutes? 
statistics
The average scuba diver can stay under water for 42 minutes with a standard deviation of 8 minutes.(show graph) B. what is the probabilty that a diver stays under for the less than 53 minutes? 
6TH GRADE MATH
A sea cow can stay under water y minutes. This is 11 minutes longer than one  third the time of a hippopotamus can. Write an equation that states the relationship of the minutes these two mammals can stay under water. Complete the … 
math
A scuba diver dove from the surface of the ocean to an elevation of 79 9/10 feet at a rate of 18.8 feet per minute. After spending 12.75 minutes at that elevation, the diver ascended to an elevation of 28 9/10 feet. The total time … 
math
A scuba diver dove from the surface of the ocean to an elevation of −99 9 10 feet at a rate of −30.7 feet per minute. After spending 14 minutes at that elevation, the diver ascended to an elevation of −8 9 10 feet. … 
math
A scuba diver dove from the surface of the ocean to an elevation of 79 9/10 feet at a rate of 18.8 feet per minute. After spending 12.75 minutes at that elevation, the diver ascended to an elevation of 28 9/10 feet. The total time … 
math
A scuba diver dove from the surface of the ocean to an elevation of −89 9 10 feet at a rate of −24 feet per minute. After spending 11.75 minutes at that elevation, the diver ascended to an elevation of −8 9 10 feet. The total … 
math
A scuba diver dove from the surface of the ocean to an elevation of ÃƒÂ¢Ã‹â€ Ã¢â‚¬â„¢89 9 10 feet at a rate of ÃƒÂ¢Ã‹â€ Ã¢â‚¬â„¢24 feet per minute. After spending 11.75 minutes at that elevation, …