Alegebra

posted by .

A physical fitness association is including the mile run in its secondary-school fitness test. The time for this event for boys in secondary school is known to possess a normal distribution with a mean of 450 seconds and a standard deviation of 50 seconds. Find the probability that a randomly selected boy in secondary school can run the mile in less than 335 seconds.

• Alegebra -

• Alegebra -

You are given the normal model N(450, 50)

Find the z score for 335 seconds.
z = (x-u)/s
where u = mu and s = sigma.

z = (335-450)/50
z = -2.3

Now use the normal cumulative distribution function on a calculator or program to find the P(z<-2.3)

normalCDF(-99,-2.3) = .0107

• Alegebra -

Marth this are my choices
A) 0.9893
B) 0.0107
C) 0.4893
D) 0.5107

So I'm assuming it's letter B? correct

• Alegebra -

Dahhhh lol

Similar Questions

1. Math

A physical fitness association is including the mile run in its secondary-school fitness test. The time for this event for boys in secondary school is known to possess a normal distribution with a mean of 450 seconds and a standard …
2. math

A physical fitness association is including the mile run in its secondary-school fitness test. The time for this event for boys in secondary school is known to posses a normal distribution with a mean of 450 seconds and a standard …
3. math

A physical fitness association is including the mile run in its secondary-school fitness test. The time for this event for boys in secondary school is known to possess a normal distribution with a mean of 450 seconds and a standard …
4. math

Can someone assit me with my two math problems Assume that the salaries of elementary school teachers in the united states are normally distributed with the mean of 36,000 and a standard deviation of 6,000. What is the cut off salary …
5. statistics

A physical fitness association is including the mile run in its secondary-school fitness test. The time for this event for boys in secondary school is known to possess a normal distribution with a mean of 440 seconds and a standard …
6. English

1. I am a freshman in high school. 2. I am a freshman of high school. (Which preposition should we use?
7. Statistics

A physical fitness association is including the mile run in its secondary-school fitness test. The time for this event for boys in secondary school is known to possess a normal distribution with a mean of 460 seconds and a standard …
8. stats

A physical fitness association is including the mile run in its secondary-school fitness test. The time for this event for boys in secondary school is known to possess a normal distribution with a mean of 460 seconds and a standard …
9. English

An upper-secondary school is a senior high school. Then is a lower-secondary school a junior high school?
10. Statistics

A physical fitness association is including the mile run in its secondary-school fitness test for boys. The time for this event for boys in secondary school is normally distributed with a mean of 450 seconds and a standard deviation …

More Similar Questions