Answer:
We need to remember that we have independent events when a given event is not affected by previous events, and we can verify if two events are independnet with the following equation:

For this case we have that:

And we see that 
So then we can conclude that the two events given are not independent and have a relationship or dependence.
Step-by-step explanation:
For this case we can define the following events:
A= In a certain computer a memory failure
B= In a certain computer a hard disk failure
We have the probability for the two events given on this case:

We also know the probability that the memory and the hard drive fail simultaneously given by:

And we want to check if the two events are independent.
We need to remember that we have independent events when a given event is not affected by previous events, and we can verify if two events are independnet with the following equation:

For this case we have that:

And we see that 
So then we can conclude that the two events given are not independent and have a relationship or dependence.
Answer:
b=20 yards
Step-by-step explanation:
15^2+x^2=25^2
225+x^2=625
x^2=400
x=20
Answer:
17
Step-by-step explanation:
Using the law of cosines in ΔABC
b² = a² + c² - (2ac cosB) ← substitute in values
= 25² + 28² - (2 × 25 × 28 × cos36.9°)
= 625 + 784 - 1400 cos36.9°
= 1409 - 1400 cos36.9° ( Take the square root of both sides )
b =
≈ 17 ( nearest whole number )
I assume you're looking for the number:
0.5n + 9 = 21
- 9
0.5n = 12
÷ 0.5
n = 24
So the beginning number is 24, hope this helps!
when you subtract numbers with three digits its almost exactly the same as regular subtracting but with decimals.