Answer:
the probability that the sample variance exceeds 3.10 is 0.02020 ( 2,02%)
Step-by-step explanation:
since the variance S² of the batch follows a normal distribution , then for a sample n of 20 distributions , then the random variable Z:
Z= S²*(n-1)/σ²
follows a χ² ( chi-squared) distribution with (n-1) degrees of freedom
since
S² > 3.10 , σ²= 1.75 , n= 20
thus
Z > 33.65
then from χ² distribution tables:
P(Z > 33.65) = 0.02020
therefore the probability that the sample variance exceeds 3.10 is 0.02020 ( 2,02%)
Answer:
Last equation given in the list of possible answers:
5 ( 1.5 + 1.5 + x ) = 25
Step-by-step explanation:
We need to include in the total addition of miles ridden during the week:
a) 1.5 miles to the school
b) 1.5 miles from school back home
c) x miles for the evening ride
so for the miles ridden per day we have: "1.5 +1.5 + x"
Now, since per week she does 5 days like this, then we need to multiply the expression above by 5 in order to total the number of miles she rides weekly (25 miles)
5 ( 1.5 + 1.5 + x ) = 25
And we can use this equation to find the amount "x" that Rin rides in the evening.
The formula of the length of the segment AB:
We have:
Substitute:
Answer:
B) 10.
B is the answer I think but so t take my word for it
Here we're applying a basic physics rule for vertical motion where the only pull on the object is gravity.
This rule has the form
h(t) = h + v t + (1/2)a*t^2
o o
To adapt this rule to this particular question replace h with 0, as the
o
upward path of the object begins at 0 ft. Replace v with +15 ft/sec.
o
Replace "a" with (-32.2 ft/(sec^2); this is the acceleration due to gravity.
Then we have the following, with the label F(t):
F(t) = 0 + (15 ft/sec)t + (1/2)(-32.2 ft)/(sec^2), or
F(t) = 15t - 16.1t^2. Thus, Choice D is correct.
Please note: To avoid confusion, please use " ^ " to denote exponentiation:
F(t) = -16t^2 + 15t
