Answer:
x = 6
Step-by-step explanation:
The scale factor is
28/8 = 7/2
We take the ratio of the larger side over the smaller side
Using ratios we can find the sides
28 21
----- = ---------
8 x
Using cross products
28x = 21*8
28x =168
Divide each side by 28
28x/28 = 168/28
x =6
You know that 3 times 2 is 6 so 30'times 20 equals 60
Answer:
71.123 mph ≤ μ ≤ 77.277 mph
Step-by-step explanation:
Taking into account that the speed of all cars traveling on this highway have a normal distribution and we can only know the mean and the standard deviation of the sample, the confidence interval for the mean is calculated as:
≤ μ ≤ 
Where m is the mean of the sample, s is the standard deviation of the sample, n is the size of the sample, μ is the mean speed of all cars, and
is the number for t-student distribution where a/2 is the amount of area in one tail and n-1 are the degrees of freedom.
the mean and the standard deviation of the sample are equal to 74.2 and 5.3083 respectively, the size of the sample is 10, the distribution t- student has 9 degrees of freedom and the value of a is 10%.
So, if we replace m by 74.2, s by 5.3083, n by 10 and
by 1.8331, we get that the 90% confidence interval for the mean speed is:
≤ μ ≤ 
74.2 - 3.077 ≤ μ ≤ 74.2 + 3.077
71.123 ≤ μ ≤ 77.277
Answer:
A.105°
Step-by-step explanation:
Angle at W and V are equal and the angles at T and U are also equal
Hence taking angles at T and U...so as to calculate the value of x
5x + 15 = 3x + 21
5x - 3x = 21 - 15
2x = 6.....hence, x = 3
Then for the angle of VXU;
All angles in a triangle add up to 180°
15(3) + 3(3) + 21 = 75°...then subtract from 180°..so as to obtain angle at VXU
180 - 75 = 105°