Ask question

Ask question

All categories

3 years ago

7

the times a fire department takes to arrive at the scenes of an emeregency are normally distributed with a mean of 6 minutes and

a standard deviasion of 1 minute. for about what percent of emergencys does the fire arrive at the scene in 4 minutes or less

1 answer:

Dvinal [7]3 years ago

5 0

Answer:

cool whats the question tho?

You might be interested in

Find the 6th term of GP whose 1st term is 32 and 2nd term is 8

Oliga [24]

Answer:

c = 1/32

Step-by-step explanation:

32-x-x-x-x-x-x-x

32/4 = 8

so product 1/4 is the rule

32/4^5= 2^5/2^10

2^-5=1/32

3 0

2 years ago

If 90 percent of automobiles in Orange County have both headlights working, what is the probability that in a sample of eight au

Alex17521 [72]

Answer:

$P(X \geq 7) = P(X=7) +P(X=8)$

And we can find the individual probabilities using the probability mass function

$P(X=7)=(8C7)(0.9)^7 (1-0.9)^{8-7}=0.3826$

$P(X=8)=(8C8)(0.9)^8 (1-0.9)^{8-8}=0.4305$

And replacing we got:

$P(X \geq 7) = P(X=7) +P(X=8)=0.3826 +0.4305=0.8131$

Step-by-step explanation:

Previous concepts

The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".

Solution to the problem

Let X the random variable of interest "number of automobiles with both headligths working", on this case we now that:

$X \sim Binom(n=8, p=0.9)$

The probability mass function for the Binomial distribution is given as:

$P(X)=(nCx)(p)^x (1-p)^{n-x}$

Where (nCx) means combinatory and it's given by this formula:

$nCx=\frac{n!}{(n-x)! x!}$

And for this case we want to find this probability:

$P(X \geq 7) = P(X=7) +P(X=8)$

And we can find the individual probabilities using the probability mass function

$P(X=7)=(8C7)(0.9)^7 (1-0.9)^{8-7}=0.3826$

$P(X=8)=(8C8)(0.9)^8 (1-0.9)^{8-8}=0.4305$

And replacing we got:

$P(X \geq 7) = P(X=7) +P(X=8)=0.3826 +0.4305=0.8131$

3 0

2 years ago

Read 2 more answers

Of the 600 sixth graders at Melville Middle School, 80% want more field trips. How many students want more field trips? Use the

irga5000 [103]

Answer:

480 students want more field trips.

60 students is 10%.

Step-by-step explanation:

There are 600 students, and 80% want more field trips.

80% of 600 is 0.8*600 = 8*60 = 480 students.

480 students want more field trips.

6 0

2 years ago

8m/3 = 6/11 ?!?!?!?!?!?!?!?!?!?!?!?!!??!?!?!?!?!?!?!??!

GalinKa [24]

Answer:

cross multiply

(8m)(11)=(6)(3)

88m=18

then divide by 88 on both sides

m=18/88 then reduce by 2 -----> 9/44

Step-by-step explanation:

5 0

3 years ago

Brian is solving the equation x^2 - 3/4x= 5. What value must be added to both sides of the equation to make the left side a perf

Yakvenalex [24]

<span>((-3/4)/2)^2 = 9/64 I HOPE THIS HELP</span>

5 0

3 years ago

Read 2 more answers