Answer:
Both ratios reduce to the same ratio 3/50, so the restocking fee is proportional.
Step-by-step explanation:
For the $200, the restocking fee is $12, so the ratio of the restocking fee to the price of the item is 12/200.
For the $150, the restocking fee is $9, so the ratio of the restocking fee to the price of the item is 9/150.
Now we find out if the ratios 12/200 and 9/150 are equal.
12/200 = 3/50
9/150 = 3/50
Both ratios reduce to the same ratio 3/50, so the restocking fee is proportional.
(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%
Answer:
B
Step-by-step explanation:
Answer:
a(8) = -0.0027
Step-by-step explanation:
The most general formula for a geometric sequence is a(n) = a(1)*r^(n-1), where a(1) is the first term and r is the common ratio.
Here, the formula becomes a(n) = 6*(-1/3)^(n-1).
Substitute 8 for n to find the eighth term:
a(8) = 6*(-1/3)^(8-1), or a(8) = 6(-1/3)^7, or a(8) = -0.0027
