Answer:
Step-by-step explanation:
Since the length of time taken on the SAT for a group of students is normally distributed, we would apply the formula for normal distribution which is expressed as
z = (x - u)/s
Where
x = length of time
u = mean time
s = standard deviation
From the information given,
u = 2.5 hours
s = 0.25 hours
We want to find the probability that the sample mean is between two hours and three hours.. It is expressed as
P(2 lesser than or equal to x lesser than or equal to 3)
For x = 2,
z = (2 - 2.5)/0.25 = - 2
Looking at the normal distribution table, the probability corresponding to the z score is 0.02275
For x = 3,
z = (3 - 2.5)/0.25 = 2
Looking at the normal distribution table, the probability corresponding to the z score is 0.97725
P(2 lesser than or equal to x lesser than or equal to 3)
= 0.97725 - 0.02275 = 0.9545
You can combine the same numbers with the same variables using the operation sign for each. For example, using your equation, you would combine the 3n and 4n which is 7n. So your equation would be
7n - 2
Answer:
(2,3)
Step-by-step explanation:
Okay, to find length CE, your going to know the value of <em>x</em>. Length BC + CE = BD + DE.
3x+47+x+26=27+x+10
Simplify the equation to get
4x+73=37+x
you can choose one of four ways to continue, but I will choose to subtract x
3x+73=37
Subtract 73 from both sides of the equal sign
3x=-36
divide by 3 on both sides of the equal sign to get the value of x
x=-12
Now, plug in -12 for x in length CE to get -12+26=14
