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%)
The formula for surface area of a sphere: A = 4 pi r^2.
Since the radius is 30 m then A = 4pi30^2.
30^2 x 4 =3600
A=3600pi m
Step-by-step explanation:
BE/BC=BD/BA
tHE TWO SIMILAR TRIANGLES ARE BED AND BC. tHE PROPORTION ABOVE REPRESENTS USE OF THE TWO SIMILAR TRIANGLES.
4/(4 + 10) = 5/(5+X) Cross Multiply
4(5+x) = 5(4+10)m
20 +4x=20 +50 subtract 20 from both sides
4x = 50 divide by 4
x =12.5
Y=3x-5
y-3x=-5
Times 2 from both side
y(2)-3x(2)=-5(2)
2y-6x=-10
Times negative from both side
(-)2y-6x(-)=(-)-10
-2y+6x=10
or
6x-2y=10
6x=2y+10
6x-2y=10
Furthermore, we see that both equation have the same 6x-2y=10 which means that both of them have infinity solutions, not a solution. Hope it help!
Answer:

Step-by-step explanation:
From the question, Diana wants her total bill to be less than $50.
Diana pays a fixed monthly bill of
$39 for her mobile phone and an additional
$0.15 per minute for phone internet service.
The bill Diana pays for m minutes of using the internet is $0.15m in a month.
The total monthly bill becomes,

The maximum bill she wants to pay is $50.

This inequality can be solved to determine the number of available minutes.