(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%
4x = 32 - 2x
Add -2x (or subtract 2x) from each side
2x = 32
Divide both sides by 2
x = 16
Answer:
a) y = 6x - 3
b) 1/3y = 2x -1
The first thing you need to do is isolate (y) in the second equation
3 x (1/3y) = 3 x (2x - 1)
y =6x - 3
After isolating (y) in equation b they end up being the same.
Graphing:
In order to graph this, you have to make the first point at (0, -3) since this is the Y-intercept of the equation.
In order to graph the other points, you must move 6 units up and 1 unit to the right. Or vise versa If you need a visual I'll gladly link one.
Answer:
The speed with which Ryan was rowing was 4 mph
Step-by-step explanation:
With a small boat, Ryan wants to row towards an island and come back at a speed of x mph and the island is 20 miles away from him.
Therefore, total 20 + 20 = 40 miles he rowed for 5 hours.
On the way to the island, there was a wind of 4 mph in the direction of his motion and on the way back also there was a wind of 4 mph in the direction of his motion.
So, in the total journey, he has a speed of (x + 4) mph.
Therefore, 
⇒ x + 4 = 8
⇒ x = 4 mph.
Therefore, the speed with which Ryan was rowing was 4 mph. (Answer)
Answer:
See explanation
Step-by-step explanation:
Polygon WXYZ has vertices W(-1.5, 1.5), X(6, 1.5), Y(6, -4.5), and Z(-1.5, -4.5).
Find the slopes of all sides:
- horizontal line
- slope undefined, so the line is vertical
- horizontal line
- slope undefined, so the line is vertical
Vertical and horizontal lines are perpendicular, so all angles W, X, Y and Z are right angles. Hence, quadrilateral WXYZ is a rectangle
