Answer:
0.7233
Step-by-step explanation:
We want to find the area between the z-scores z=-0.95 and z=1.25.
We first find the area to the left of each z-score, and subtract the smaller area from the bigger one.
For the area to the left of z=-0.95, we read -0.9 under 5 from the standard normal distribution table.
This gives P(z<-0.95)=0.1711
Similarly the area to the left of z=1.25 is
P(z<1.25)=0.8944
Now the area between the two z-scores is
P(-0.25<z<1.25)=0.8944-0.1711=0.7233
Answer:
x=1/5
Step-by-step explanation:
-5x-(-7-4x)=-2(3x-4)
-5x+7+4x=-6x+8
-5x+4x+7=-6x+8
-x+7=-6x+8
-x-(-6x)+7=8
-x+6x+7=8
5x+7=8
5x=8-7
5x=1
x=1/5
Answer:
C. 45 and 141 seconds
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 93 seconds
Standard deviation = 16 seconds
99.7% of running times are approximately between:
By the Empirical rule, within 3 standard deviations of the mean, so between 3 standard deviations below the mean and 3 standard deviations above the mean
3 stnadard deviations below the mean
93 - 3*16 = 45 seconds
3 standard deviations above the mean
93 + 3*16 = 141 seconds
The correct answer is:
C. 45 and 141 seconds
Answer and Step-by-step explanation: Scaterplot is a type of graphic which shows the relationship between to variables. In this question, you want to determine if there is a linear relationship between overhead widths of seals and the weights. So, the hypothesis are:
H₀: no linear correlation;
H₁: there is linear correlation;
In this hypothesis test, to reject H₀, the correlation coefficient r of the data set has to be bigger than the critical value from the table.
With α = 0.05 and n = 6, the critical value is 0.811.
The linear correlation is calculated as:
r = n∑xy - ∑x.∑y / √[n∑x² - (∑x)²] [n∑y² - (∑y)²]
r = 
r = 0.9485
Since r is bigger than the critical value, H₀ is rejected, which means there is enough evidence to conclude that there is linear correlation between overhead widths and the weights.
In the attachments is the scaterplot of the measurements, also showing the relationship.