hard · GRE Quant
Reaction times are normally distributed with mean 400 milliseconds and standard deviation 25 milliseconds. Use the approximation that 34% lie between the mean and one standard deviation on either side, 14% lie between one and two standard deviations on either side, and 2% lie beyond two standard deviations in either tail. Approximately what percent of reaction times are between 425 and 450 milliseconds?
- 2%
- 14%
- 16%
- 34%
- 48%
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