Final answer:
To assess the effectiveness of an aerobics fitness program that aimed to lower heart rate, a statistical hypothesis test would be used. If a calculated z-score for the group mean heart rate after the program is greater than the tabulated value at a 10% significance level, the program is effective in lowering heart rate (Yes). Otherwise, the results would be inconclusive or negative.
Step-by-step explanation:
The question at hand is to determine whether an aerobics fitness program has effectively lowered the heart rate in a group compared to the average American heart rate of 72 beats/minute. Using a statistical hypothesis test comparing the post-program group mean of 69 beats/minute to the national average, with a standard deviation of 6.5, for 55 individuals, and a significance level of 10% (with tabulated value 2.56), we can assess the effectiveness of the program.
To determine if the change is significant, we would compute a z-score for the sample mean and compare it with the tabulated value. However, as no specific hypothesis testing steps are provided with z-score calculation, and only the significance level and tabulated value are given, we can conclude that if the calculated z-score is greater than the tabulated value, the program had a significant effect. If this is confirmed, then the answer is that the aerobics program was effective (a. Yes). If the z-score does not exceed the tabulated value, the result would be inconclusive or negative depending on the specific value attained.