Median is the number in the middle when all the numbers are put in order.
Let's do that first.
30 52 61 65 68 68 69 75 78 85
Now if there's 10 numbers, 2 numbers are in the middle.
By counting in 4 on both sides, we know the two numbers are both 68, so 68 is the median.
Answer:
Here is your answer
Step-by-step explanation:
Step -1: Forming equations.
Let, present age of son = x
And, present age of father = 3x+3
3 years later, age of son = x+3
age of father = 3x+3+3=3x+6 ...(i)
According to the given condition, age of father = 10+2(x+3) ...(ii)
Step -2: Solving for x
From (i) and (ii)
∴3x+6=10+2(x+3)
⇒3x+6=10+2x+6
⇒3x−2x=10+6−6
⇒x=10
∴Present age of son = 10
and present age of father = 3x+3=3×10+3=33
Hence, son’s present age is 10 years and father’s
(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:
65
Step-by-step explanation:
You multiply the factors by each other.