Answer How many liters of a 20% acid solution should be mixed with 30 liters of 50% acid solution in order to obtain a 40% solution. ... x=15 liters 15*(.20 pure acid)=3 liters 30*(.50 pure acid)=15 liters That is 18 liters pure acid That is 45 liters solution *0.45 pure acid=18 liters.
As more pure acid is added, the concentration of acid approaches 0.
Answer:
The test statistic value is 15.3.
Step-by-step explanation:
The hypothesis for this test is:
<em>H</em>₀: The average number of homeless people is not increasing, i.e. <em>μ</em> = 42.3.
<em>H</em>ₐ: The average number of homeless people is increasing, i.e. <em>μ</em> > 42.3.
Given:

As the population standard deviation is provided use a single mean <em>z</em>-test for the hypothesis testing.
The test statistic is:

Thus, the test statistic value is 15.3.
Answer:
Systematic error
Step-by-step explanation:
Assuming that none of the judges are biased, the most likely reason for this difference is the occurrence of systematic errors.
Systematic errors are errors introduced by inaccuracy in the experimental design, be it in the observation or measurement process.
In this case, the reaction time from observing the finish and stopping the clock for each judge might be different, which configures a systematic error.