(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%
The answer is either 
or 
To solve: Let's solve your equation step-by-step.
5x2+5x−x2−x=2004
Step 1: Simplify both sides of the equation.
4x2+4x=2004
Step 2: Subtract 2004 from both sides.
4x2+4x−2004=2004−2004
4x2+4x−2004=0
Step 3: Use quadratic formula with a=4, b=4, c=-2004.
x=
−b±√b2−4ac
/2a
x=
−4±√32080
/8
or
Answer:
8.66214 x 10^11
Step-by-step explanation:
question may ask to round, so the answer may be simplified to 9 x 10^11
If two positive angles have a sum of 180 degrees, they are called supplementary angles.
She needs to ride 46 miles . to get this answer you multiply 61 by 6 and get 366. then you add up all the numbers and get 320 then you subtract 366 by 320 .
