But in Africa's case, efforts must be quadrupled or quintupled.

ECONOMIST: The UN's Millennium Development Goals

Ted Cruz, R-Texas, later tried to require that the number of U.S. border patrol agents be tripled on the U.S.-Mexico border and the amount of equipment stationed there be quadrupled before any immigrant could apply for a change in legal status.

NPR: Coalition On Immigration Bill Clears First Tests

If the technique proved successful in resuscitating hearts that were currently unusable the number of transplants could be tripled or quadrupled, he added.

BBC: NEWS | Health | Beating-heart transplant UK first

It could easily be doubled, or quadrupled, by 2016.

NEWYORKER: Schmooze or Lose

It cannot be doubled, tripled or quadrupled.

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You just had to be smart enough to make the right choices so that your money quadrupled overnight, then you quit.

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