Answer:
4.75% probability that the line pressure will exceed 1000 kPa during any measurement
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:

What is the probability that the line pressure will exceed 1000 kPa during any measurement
This is 1 subtracted by the pvalue of Z when X = 1000. So



has a pvalue of 0.9525
1 - 0.9525 = 0.0475
4.75% probability that the line pressure will exceed 1000 kPa during any measurement
32%, because you divide 8 by 25, which is 0.32. You then multiply it by 10 to achieve the percentage.
7 * 0.5 + 3 * 0.8 = 3.5 + 2.4 = 5.9
<span>5.9/10 X 100 = 59%
</span><span>59% concentration of new mixture</span>