A and can I be brainliest? :3
Answer:
The answer is:
30 minutes.
Step-by-step explanation:
We are given the following information:
at 160 m/min, tool life = 5 min.
at 120 m/min, tool life = 17 min.
This means that as the speed reduced from 160 m/min to 120 m/min, the tool life increased from 5 min. to 17 min, hence the difference between the changes are:
speed = 160 - 120 = 40 m/min
tool life = 17 - 5 = 12 min.
Therefore, it can be concluded that a change of speed of 40 m/min, increases the tool life by 12 min.
40 m/min = 12 min
∴ 1 m/min = 12/40 min.
∴ 100 m/min = 12/40 × 100 = 0.3 × 100 =30 min.
Answer:
By the Empirical Rule, 
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
The symbol of a standard deviation is
. So
When plotting sample statistics on a control chart, 99.7% of the sample statistic values are expected to fall within plus/minus how many sigma?
By the Empirical Rule, 