A and B are dependent events.
The general probabilities of each event to happen separately is 36% for event A and 25% for event B. When considering that Chris passes one before passing the other, indicates that whether he gets the first light open or not will affect if he gets the other one also open or not. This can even be seen by noticing how the probability of Chris getting both red lights is 9%, a much inferior probability then considering both lights separately which means that one event has influence over the other.
72 divided by 9 = 8
8 + 4x4 = 8+16
8+16=24
All of them except the second one .
We have the representation of this problem in the figure below. As we have a 10.3 mile race, then the equation is fulfilled as:

We know that there is <span>a water station that is twice as far from the starting line as from the finish line, then:
</span>

So:

∴

and

<span>Finally, the distance of the runner from the finish line is:
</span>
Answers:
- a = 475
- r = -0.5
- f(3) = 59.4
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Explanation:
Any exponential function is of the form y = a*b^x
Comparing that to y = 475*(0.5)^x, we see that a = 475 and b = 0.5
Set b equal to 1+r and solve for r
1+r = 0.5
r = 0.5-1
r = -0.5
The negative r value tells us that the growth rate is -50%, in other words, we have a 50% decay rate. The amount drops by 50% each time x goes up by 1. This is the same as saying the amount cuts in half each time x goes up by 1.
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Lastly, plug in x = 3 to find f(3)
f(x) = 475(0.5)^x
f(3) = 475(0.5)^3
f(3) = 59.375
f(3) = 59.4