Re: Quantitative Reasoning - Compound Interest
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02 Sep 2019, 08:15
In 12 years the investment quadrupled (from $1,000 to $4,000).
Thus, at the same rate compounded annually, it would need additional 12/2=6 years to double (from $4,000 to $8,000).
Therefore, 12+6=18 years are needed $1,000 to increase to $8,000.
Answer: B.