Solution of problem N1013 Laplace probability theory

Solution of problem N1013 Laplace probability theory

1013. The probability that a dealer trading in securities will sell them is 0.7. How much securities should be in order to be able to affirm with a probability of 0.996, that the share sold among them will deviate from 0.7 to no more than 0.04 (in absolute value)?

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Detailed solution. Decorated in Microsoft Word 2003 (Quest decided to use the formula editor)