An unpublished statistics book

You take out your trusty calculator and try several combinations of numerators with denominators of 153 and 147 and see which, if any, of them yield 69.8% (rounded to the nearest tenth of a percent). OR, you can use a book of tables, e.g., the book by Stone (1958), and see what kinds of percentages you get for what kinds of n’s. ................
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