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DR Medhat MRCP

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Q : A study is performed to find the normal reference range for IgE levels in adults.<br />

Assuming IgE levels follow a normal distribution, what percentage of adults will<br />

have an IgE level above 2 standard deviations from the mean?<br />

A : For normally distributed data 95.4% of values lie within 2 standard deviations of the<br />

mean, leaving 4.6% outside this range →Therefore 2.3% of values will be higher and<br />

2.3% will be lower than 2 standard deviations from the mean.<br />

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