Final answer:
After falling back to Brooklyn, Washington's plan involved deceiving the British by pretending the new troops were his entire army while his actual army silently retreated to Manhattan.
Step-by-step explanation:
After falling back to Brooklyn, Washington devised a plan to escape from the British. He had the new troops essentially pretend to be his entire army, while his actual army silently retreated under the cover of darkness and rain. The campfires were kept lit to deceive the British, making them think the Americans were still in position. By the time the British realized Washington's army was gone, he and his entire army of 9,000 soldiers were safely in Manhattan.