Scores in a standardized exam are normally distributed with mean μ = 510 and standard deviation σ = 60. The middle 75% of scores are classified as “average”. Find the range of scores that are average according to this definition.
"\\mu=510,\\sigma=60"
Middle 75% are classified as avergae-
"\\alpha=0.25"
"z_{\\frac{\\alpha}{2}}=z_{0.125}=1.1503"
Confidence Interval "= \\mu\\pm z_{0.125}\\times 60"
"=510\\pm 1.1503\\times 60\\\\=(510\\pm 69.018)\\\\=(440.98,579.018)"
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