Answer:
-12.5%
Step-by-step explanation:
The percentage change in your time can be computed using ...
pct change = ((new value)/(old value) -1) × 100%
= (28/32 -1) × 100%
= (0.875 -1) × 100% = -12.5%
The time to finish level 2 decreased by 12.5%.
Using the z-distribution, the p-value would be given as follows:
b) 0.0086.
<h3>What are the hypothesis tested?</h3>
At the null hypothesis we test if the means are equal, hence:
At the alternative hypothesis, it is tested if they are different, hence:
<h3>What are the mean and the standard error for the distribution of differences?</h3>
For each sample, they are given as follows:
Hence, for the distribution of differences, they are given by:
.
<h3>What is the test statistic?</h3>
The test statistic is given by:
In which 
is the value tested at the null hypothesis.
Hence:
z = -2.63.
Using a z-distribution calculator, for a two-tailed test, with z = -2.63, the p-value is of 0.0086.
Hence option B is correct.
More can be learned about the z-distribution at brainly.com/question/13873630
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Answer:
7/10
Step-by-step explanation:
Total number = 17+3+8+12 = 40
The ones that are large are 17 and 8
The ones that are blue are 17 and 3
Do not count the 17 twice
P(large or blue) = (17+3+8)/40
= 28/40
=7/10
Possible unit is m³
<u>Step-by-step explanation:</u>
- The possible unit for volume of a cone is m³
- Volume of a cone = Base area × Height
- Here unit for volume will be square units and that of height will be in units. Together, they form cubic units.
- In the given options, the only unit that is in cubic form is m³
I think that is the mean or the mode . I think more on mean
