Answer:
The probability that a call last between 4.2 and 4.9 minutes is 0.4599
Step-by-step explanation:
Let X be the length in minutes of a random phone call. X is a normal distribution with mean λ=4.2 and standard deviation σ=0.4. We want to know P(4.2 < X < 4.9). In order to make computations, we will use W, the standarization of X, given by the following formula
We will use 
, the cummulative distribution function of W. The values of are well known and the can be found in the attached file
We conclude that the probability that a call last between 4.2 and 4.9 minutes is 0.4599
Answer:
a. 
u1≤u2
b P<0.05 rejected H
Step-by-step explanation:
College High School
485 442
534 580
650 479
554 486
550 528
572 524
497 492
592 478
487 425
533 485
526 390
410 535
515
578
448
469
The mean is the average . the sum of number over the number of observation
x1=525
x2=487
s.d1=59.42
s.d2=51.74
n1=16
n2=12
Determine the hypothesis
u1≤u2
find the degree of freedom
25
p-value is the probability of obtaining the value of the test statistics. In the column of t-value in the row df=25
0.025<P<0.05
if the P value is actually less than or the same as the significant level, then the null hypothesis is rejected
P<0.05 rejected H
Answer:
x≈-2.433 ,x≈2.15
Step-by-step explanation:
Answer:
Then, the area of the right angle triangle AED is 84in^2.
Step-by-step explanation:
The triangle AED is a right angle triangle
And the area of a triangle is given as
Area=1/2base ×height
The base is 14in
And the height is 12in
Then,
Area=1/2base ×height
Area = 1/2 ×14 ×12
Area = 84in^2
Then, the area of the right angle triangle AED is 84in^2.
Answer:
51.81 cm^2
Step-by-step explanation:
Find The Half Of 33 which is 16.5
Use The Formula For Area
A= 
x r^2
A= 3.14 x 16.5
A= 51.81 cm^2
