In a normal distribution, 8% of items are under 50 and 10% are over 60. Find the mean and standard deviation of the distribution.
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Value of Z, corresponding to 0.5-0.08=0.42 are , is equal to 0.202
"0.202=\\dfrac{50-\\mu}{\\sigma}"
"\\Rightarrow \\mu-0.202\\sigma=50~~~~~~~~~-(1)"
Value of Z, corresponding to 0.5-0.10=0.40 are , is equal to 0.253
"0.253=\\dfrac{60-\\mu}{\\sigma}"
"\\Rightarrow \\mu-0.253\\sigma=60~~~~~~~~~-(2)"
Solving equation 1 and 2 we get-
"\\mu=10.39\\\\\n\n \\sigma=2.53"
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