Answer:
It decreases.
Step-by-step explanation:
10 / d
Lets say that it was 10 / 40, which is 10 divided by 40, 0.25.
Now, it has increased to twice the amount of that.
1 / 80, 10 divided by 80, which is 0.125
So, it decreases.
Answer:
B
Step-by-step explanation:
Because the rest are wrong. It is just asking you to compare the numbers. choice B says that Group 1/A needs 6 more lessons than Group 12/B
Answer:
The 90% confidence interval for the true mean lifespan of this product is between 13.1 and 16.9 years.
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 50 - 1 = 49
90% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 49 degrees of freedom(y-axis) and a confidence level of
. So we have T = 1.6766
The margin of error is:

In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 15 - 1.9 = 13.1 years
The upper end of the interval is the sample mean added to M. So it is 15 + 1.9 = 16.9 years
The 90% confidence interval for the true mean lifespan of this product is between 13.1 and 16.9 years.
576577 is the right answer and the right to
Answer:
1
Step-by-step explanation:
There is an important trig identity which you must know: (sin x)^2 + (cos x)^2 = 1.
Therefore, sin^2(20°)+cos^2(20°) = 1