From a large consignment of apples, 400 apples were selected randomly and out of these 65 apples were found to be defective. Find the Standard Error of proportion of bad apples in the consignment.

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You need to use the following formula to evaluate the standard error of proportion, such that:

`SE = sqrt(p(1 - p)/n)`

You may evaluate p such that:

`p = 65/400 => p = 13/80 => p = 0.1625`

`1 - p = 1 - 0.1625 => 1 - p = 0.8375`

Replacing `0.1625` for `p,0.8375` for `1 - p` and 400 for n, yields:

`SE = sqrt(0.1625*0.8375/400) => SE = 0.018445443`

**Hence, evaluating the standard error of proportion, under the given conditions, yields **`SE = 0.018445443.`

Also determine the range of proportion within which the population proportion would lie with 95% confidence.

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