Jenna's age Jessica's age
today x x + 5
in 5 years x+5
5 years ago x + 5 - 5
Equality x + 5 = x + 5 - 5
=> x + 5 = x
The equation is x + 5 = x
That equation has not any solution, because it reduces to 5 = 0, which is an absurd.
So, the conclusion is that information given by Jenna is wrong.
It is logical: if the difference of the ages is 5, in five years Jenna will have 10 years more than what her sister had 5 years ago, no 5 as she told Jessica.
Answer: 12 inches
Step-by-step explanation: In this problem, since we're asked to find the length of the median, let's use our formula for the area of a trapezoid that involves the median which is shown below.
Area = median · height
We know that the area is 144 and the height is 9 so we can set up the equation 144 = M · 12. Now to solve for <em>m</em>, we divide both sides of the equation by 12 and we find that 12 = M.
So the length of the median of the trapezoid is 12 inches.
P=i/rt
P=1687.5/(0.09*10/12)
P=22500
Answer:
a) 0.0228
b) 94.6
Step-by-step explanation:
The formula for calculating a z-score when you are given a random.number of samples is z = (x-μ)/σ/√n
where x is the raw score
μ is the population mean
σ is the population standard deviation
n = random number of samples
Given a normal distribution with u = 75 and o = 40, if you select a sample of n = 16,
a) what is the probability that the sample mean is above 95? (4 d.p.) b)
= x = 95
Hence:
z = 95 - 75/40/√16
= 20/40/4
= 20/10
= 2
Probability value from Z-Table:
P(x<95) = 0.97725
P(x>95) = 1 - P(x<95) = 0.02275
The probability that the sample mean is above 95 to 4 decimal places = 0.0228
b) What is the value, of which there is 97.5% chance that a sample mean is less than that value?
97.5% chance = z score for the confidence interval = 1.96
Hence:
z = (x-μ)/σ/√n
1.96 = x - 75/40/√16
1.96 = x - 75/ 40/4
1.96 = x - 75/10
Cross Multiply
1.96 × 10 = x - 75
19.6 = x - 75
x = 19.6 + 75
x = 94.6
The value, of which there is 97.5% chance that a sample mean is less than that value is 94.6
