medium · GRE Quant
For grip strength in an ergonomics field study, values are normally distributed with mean 45 and standard deviation 9. 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%. The middle 68% of the values lie between which two numbers?
- 27 and 63
- 31.5 and 58.5
- 18 and 72
- 40.5 and 49.5
- 36 and 54
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