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.
Answer: slope =1/2 y intercept (0,6)
Step-by-step explanation: use the slope and y intercept form y=mx + b
1/2 = 0.5
Proof:
1/4 + 1/4 = 2/4 = 1/2 = 0.25 + 0.25 = 0.50
150 what? are you saying 150 mins or 1.50 mins?