I think its C im not sure if im right though.
Answer:
45,45,90
Step-by-step explanation:
3x + 3x + 6x= 180
12x=180
x= 180/12= 15
3x=3×15=45
3x=3×15=45
6x=6×15=90
Answer:
16 times
Step-by-step explanation:
Answer:
2.28% of the class has a lower heart rate
Step-by-step explanation:
Problems of normally distributed samples can be solved using the z-score formula.
In a set with mean
and standard deviation(which is the square root of the variance)
, 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 percent of the class has a lower heart rate
Lower than 72, which is the pvalue of Z when X = 72.



has a pvalue of 0.0228
2.28% of the class has a lower heart rate
Answer:
20%
Step-by-step explanation: