Answer:
131.2 ;
12.8 ;
(118.4, 144)
Step-by-step explanation:
Given :
X = 131.2, s=55 , and n= 50
Point estimate of the mean :
Since, sample size is large (n > 30) ; the sample mean = population mean according to the center limit theorem :
Margin of Error = Zcritical * s / sqrt(n)
Zcritical at 90% = 1.645
Margin of Error : 1.645 * (55 / sqrt(50))
Margin of Error : 1.645 * 7.7781745
Margin of Error = 12.795097
Margin of Error = 12.8
The confidence interval (C.I) :
C.I = x ± margin of error
C. I = 131.2 ± 12.8
(131.2 - 12.8) ; (131.2 + 12.8)
(118.4, 144)
Commutative property of multiplication
3/10 is it because the greatest common factor is 2.
0.92085175 radians
Let's first calculate the length of the diagonal of the base. Using the Pythagorean theorem:
b = sqrt(9^2 + 7^2) = sqrt(81 + 49) = sqrt(130) = 11.40175425
Now the length of the diagonal to the box. Once again, using the Pythagorean theorem:
d = sqrt(15^2 + 11.40175425^2) = sqrt(225 + 130) = sqrt(335) = 18.84144368
We now have a right triangle where we know the lengths of all three sides. The lengths are:
a = 15
b = sqrt(130) ≠11.40175425
c = sqrt(335) ≠18.84144368
we want the angle opposite to side a. So
tan(A) = 15/11.40175425 = 1.315587029
A = atan(1.315587029)
A = 0.92085175 radians