Answer: this is rounded out, and an estimate but...
Step-by-step explanation:
It appears to be 14.03% I could be wrong, but this was calculated so maybe not.
8 dollars per hour because 92-20=72. That the allowance you earn per week. After that you divide 72/9 because you work 9 hours to get to 72 dollars.
A suitable probability calculator can tell you the probability is about 6.7%.
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The standard deviation of the distribution of sample means is the population standard deviation (6) divided by the square root of the sample size (√144=12). Thus, your threshold is about (19.25-20)/(6/12) = -1.5 standard deviations from the mean.
Yes............................
squaring something multiplies it by itself. -4^2 = -4*-4 = 16