Quantitative经典题3.2

同学你好，

题目为：

A couple plans to pay their child’s college tuition for 4 years starting 18 years from now. The current annual cost of college is C$7,000, and they expect this cost to rise at an annual rate of 5 percent. In their planning, they assume that they can earn 6% annually. How much must they put aside each year, starting next year, if they plan to make 17 equalpayments?

题干中说明“In their planning, they assume that they can earn 6% annually”，这说明对于投资者而言，投资是以6%增长的。

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投资者在N=17时要准备一笔钱，这笔钱的目的是要足够去支付未来四年的学费。

但这笔钱不是固定不变的，而是仍然以每年6%的速率在增长。（并不是5%，5%是学费的增长速度，不是投资者手里的钱的增长速度）

折现学费的时候要考虑折现的目的，用学费的增长率折现是没有实际意义的。折现率应该是投资者手里的钱的增长率6%，这样才能保证这笔钱在17时的值，加上逐年复利所增长的份额，加在一起可以足额支付这四笔学费。

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下次提问也截个图，因为3.2题不止1个。

@GS

同学你好，提问重复了。直接参考另外一个回复即可。