Answer:
The mean speed of the automobiles traveling on this road is the closest to 65 mph.
Step-by-step explanation:
frequency distribution of speeds.
Speed (mph) | Frequency
45 up to 55 | 70
55 up to 65 | 360
65 up to 75 | 250
75 up to 85 | 110
Using the midpoint method, we represent each group/class of speeds with the midpoint speed, then go ahead to compute the mean.
Let the speed be x
The frequency be f
x | f
50 | 70
60 | 360
70 | 250
80 | 110
Mean = (Σfx)/(Σf)
Σfx = (50×70) + (60×360) + (70×250) + (80×110) = 51,400
Σf = 70 + 360 + 250 + 110 = 790
Mean = (Σfx)/(Σf)
Mean = (51400/790) = 65.06 mph ≈ 65 mph
The mean speed of the automobiles traveling on this road is the closest to 65 mph
Hope this Helps!!!
Answer:
The 90% confidence interval is
The sample size to develop a 95% confidence interval is
Step-by-step explanation:
From the question we are told that
The sample size is n =500
The sample proportion is
From the question we are told the confidence level is 90% , hence the level of significance is
=>
Generally from the normal distribution table the critical value of is
Generally the margin of error is mathematically represented as
=>
=>
Generally 90% confidence interval is mathematically represented as
=>
=>
From the question we are told the confidence level is 95% , hence the level of significance is
=>
Generally from the normal distribution table the critical value of is
The margin of error is given as
Generally the sample size is mathematically represented as
=>
=>
Answer:
2x squared +1 (-)x squared -7 is
a.) x squared +8
Step-by-step explanation:
:)
We are given number in words " two hundred fifty three thousandths".
Let us write it in number form: First we would write the number form of "two hundred fifty".
Two hundred fifty = 253.
Now, we need to write three thousandths.
Three thousandths = .003
Now, we need to combine 253 and 0.003.
On combining we get 253.003.
Answer:
Third choice, angle 5 and 2
Step-by-step explanation:
Vertical angles are opposite angles that are connected by intersecting lines.
5 and 2 are opposite angles and they are connected by, technically, two lines crossing each other.