Answer:
0.1425 = 14.25% probability that the individual's pressure will be between 119.4 and 121.4mmHg.
Step-by-step explanation:
When the distribution is normal, we use 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 question, we have that:
Find the probability that the individual's pressure will be between 119.4 and 121.4mmHg
This is the pvalue of Z when X = 121.4 subtracted by the pvalue of Z when X = 119.4. So
X = 121.4
has a pvalue of 0.5987
X = 119.4
has a pvalue of 0.4562
0.5987 - 0.4562 = 0.1425
0.1425 = 14.25% probability that the individual's pressure will be between 119.4 and 121.4mmHg.