In the story "Jack and the Beanstalk", how many beans did Jack exchange the family cow for?

Tales about climbing into the sky have been told for thousands of years in multiple countries, but the first known written account of the story appeared in England in the 1730s in the form of a skit entitled "Enchantment".

"Jack and the Beanstalk" is an English fairy tale, closely associated with the tale of "Jack the Giant Killer". It is known under a number of different versions, but the tale was popularized by Joseph Jacobs in "English Fairy Tales" (first published 1890), whose version is most commonly reprinted today. The story was made into a play by Charles Ludlam.

Summary of the story is as follows:

Young lad Jack is told by his mother to sell their family cow, which he trades to a stranger for five magic beans. Upset at this decision, Jack’s mother throws the magic beans out of the window, though they soon thereafter sprout into an enormous beanstalk that leads into a castle in the clouds.

In the castle, Jack encounters a giant woman and her giant husband. Jack decides to take some of the giants’ gold to feed his mother and himself. When Jack returns home, his mother informs him that the giant had stolen gold and treasure from Jack’s family and killed Jack’s father. Jack returns to the castle to steal back the treasures and is forced to evacuate when the giant begins to chase him down the beanstalk. Jack cuts down the beanstalk causing the giant to plummet to his death, and his family lives happily ever after.