(a) Average time to get to school
Average time (minutes) = Summation of the two means = mean time to walk to bus stop + mean time for the bust to get to school = 8+20 = 28 minutes
(b) Standard deviation of the whole trip to school
Standard deviation for the whole trip = Sqrt (Summation of variances)
Variance = Standard deviation ^2
Therefore,
Standard deviation for the whole trip = Sqrt (2^2+4^2) = Sqrt (20) = 4.47 minutes
(c) Probability that it will take more than 30 minutes to get to school
P(x>30) = 1-P(x=30)
Z(x=30) = (mean-30)/SD = (28-30)/4.47 ≈ -0.45
Now, P(x=30) = P(Z=-0.45) = 0.3264
Therefore,
P(X>30) = 1-P(X=30) = 1-0.3264 = 0.6736 = 67.36%
With actual average time to walk to the bus stop being 10 minutes;
(d) Average time to get to school
Actual average time to get to school = 10+20 = 30 minutes
(e) Standard deviation to get to school
Actual standard deviation = Previous standard deviation = 4.47 minutes. This is due to the fact that there are no changes with individual standard deviations.
(f) Probability that it will take more than 30 minutes to get to school
Z(x=30) = (mean - 30)/Sd = (30-30)/4.47 = 0/4.47 = 0
From Z table, P(x=30) = 0.5
And therefore, P(x>30) = 1- P(X=30) = 1- P(Z=0.0) = 1-0.5 = 0.5 = 50%
I'm not 100% sure this is right but I think this is how you do it
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Answer:</h2>

<h2>
Step-by-step explanation:</h2>
For a better understanding of this problem, see the figure below. Our goal is to find
. Since:

and
is a common side both for ΔMRN and ΔMQN, then by SAS postulate, these two triangles are congruent and:

By Pythagorean theorem, for triangle NQP:

Applying Pythagorean theorem again, but for triangle MQN:

Answer:
A. f(x) = 6x + 9
Step-by-step explanation:
The given equation is:
y - 6x - 9 = 0
We have to write this equation in function notation with x as the independent variable. This means that y will be replaced by f(x) and all other terms will be carried to the other side of the equation to get the desired function notation.
y - 6x - 9 = 0
y = 6x + 9
f(x) = 6x + 9
Therefore, option A gives the correct answer.
Answer:
make the numberline 800 to 0 and do bunny hop to a different part of the number line to show subtraction.
Step-by-step explanation: