medium · GRE Quant
For battery lives in a consumer-behavior experiment, values are normally distributed with mean 105 and standard deviation 12. Use the approximation that each mean-to-one-standard-deviation band contains 34%, each one-to-two-standard-deviation band contains 14%, and each tail beyond two standard deviations contains 2%. Approximately what percent of the values are from 81 through 129?
- 32%
- 34%
- 48%
- 68%
- 96%
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