Question 524270
The total value of any sum of money that earns interest at 9% doubles every 8 years. What amount of money invested now at 9% per year will accumulate to about $120000 in about 40 years?
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40 yrs is 5 8-yr periods
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60000 --> 120000
30000 --> 60000
15000 --> 30000
7500 --> 15000
3750 --> 7500
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Start with $3750
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Or,
{{{120000 = x*2^5}}}
x = 12000/32
x = $3750