We can estimate the expected value of the various percentiles assuming the normal distribution.
The median, 50th percentile, is the mean, 0.785 mm.
Typically we remember ±1 standard deviation is 68% of the probability, so one standard deviation below the mean is 16th percentile (50-68/2) and one standard deviation above the mean is 84th percentile.
The quartiles, 25th and 75th percentile, are about 2/3 of a standard deviation away from the mean. In other words ±.67 standard deviations is 50% of the probability. It's not a commonly remembered number like 68-95-99.7, but perhaps it should be.
The 25th percentile is 0.785 - (.67)(.07) = <span>0.7381 mm.
</span>The 75th percentile is 0.785 + (.67)(.07) = 0.8319 mm.
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To get 76% of 75 you turn the fraction to a decimal, then multiply it to the number. 76% as a decimal us 0.76 and 0.76 * 75 = 57
So, Ciaran got 57 out of 75 questions right.
Answer:
ummm since when did they add letters into math we ain't learning the alphabet it's math! like what
Cory visted Santa Clara, but as I can't make a table, that's all I can do.
