Lung capacity values were normally distributed with mean 3500 mL and standard deviation 300 mL. If 23% of the lung capacities were less than M's what is M's lung capacity.

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justaguide | College Teacher | (Level 2) Distinguished Educator

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The values of lung capacity are normally distributed with a mean of 3500 mL and a standard deviation of 300 mL.

23% of people have a lung capacity less than that of M. To determine the lung capacity of M, use the normal distribution table to find the corresponding z-score for 23%. This is equal to -0.74

If M's lung capacity is X, `(X - 3500)/300 = -0.74`

=> `X = 3500 - 0.74*300 = 3278`

M's lung capacity is 3278 mL.