9514 1404 393
Answer:
21.25 seconds
Step-by-step explanation:
In miles per second, the speed of the jet is ...
(720 mi/h)/(3600 s/h) = 1/5 mi/s
The speed of the sound is the same:
(1 mi)/(5 s) = 1/5 mi/s
Then the rate of closure between the airplane and the sound is ...
(1/5 mi/s) +(1/5 mi/s) = 2/5 mi/s
To find the time required to close a gap of 8 1/2 miles, we can use the relation ...
time = distance/speed
time = (8.5 mi)/(0.4 mi/s) = 21.25 s
The pilot will hear the thunder 21.25 seconds after the flash.
Answer:
y= 1x
Step-by-step explanation:
Answer:
Assuming you're referring to the sides of a right triangle, the missing side X would be 12.
Step-by-step explanation:
The Pythagorean Theorem states that the two legs of a right triangle squared and added together is equal to the hypotenuse squared.
is 169,
is 25, 169 - 25 = 144. Take the square root of 144 and you'll get 12, which is the missing side of the right triangle.
8- hundreds
9-tens
0-ones
Answer:
There is approximately 17% chance of a person not having a disease if he or she has tested positive.
Step-by-step explanation:
Denote the events as follows:
<em>D</em> = a person has contracted the disease.
+ = a person tests positive
- = a person tests negative
The information provided is:

Compute the missing probabilities as follows:

The Bayes' theorem states that the conditional probability of an event, say <em>A</em> provided that another event <em>B</em> has already occurred is:

Compute the probability that a random selected person does not have the infection if he or she has tested positive as follows:


So, there is approximately 17% chance of a person not having a disease if he or she has tested positive.
As the false negative rate of the test is 1%, this probability is not unusual considering the huge number of test done.