[beginning:\ 3x-\ apple\ juice\2x-\ orange\ juice\\ after\ delling\ 64\ bottles\ of\ apple\ juice:\ y-\ apple\ juice\ 6y-\ orange\ juice\\ 3x-64=y\ 2x=6y\ \ \ | divide\ by\ 2\ x=3y\\ 3*3y-64=y\ 9y-64=y\ \ \ | subtract\ 9y\ -64=-8y\ \ \ | divide\ by\ -8\ y=8\\ At\ the\ end\ he\ has\ 8\ apple\ juice\ and\ 48\ orange\ juice.
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Mr. Young initially had 72 bottles of apple juice and 48 bottles of orange juice. After selling 64 bottles of apple juice, he ended up with 8 bottles of apple juice and 48 bottles of orange juice. The calculations were based on the given ratios and solving simple equations step-by-step.
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