Question 324060
A=P(1+r/n)^nt
A=6000(1+0.07/4)^4*21
A=6000(1.0175)^84
A=6000*4.29429
A=25,765.72
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A=6000(1+0.07/365)^365*21
A=6000(1.000191781)^7665
A=6000*4.348628
A=26,091.77
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26091.77-25765.72=326.05 difference
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For number two A use 
A=P(1+r)^15
For two B use
A=Pe^rt
A=P*2.7183^.09*15
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Good luck