Answer :
Time taken for principal to amount to 20000 is 270 months .
Given,
Principal = 12000
Amount = 20000
Rate of interest = 2.3% compounded monthly.
Now,
C I = 20000-12000
C I = 8000
Formula for compound interest calculated monthly,
A = P(1 + (r/12)/100)^12t
Substitute the data,
20000 = 12000 (1 + (2.3/12)/100)^12t
t≅ 270 months.
Hence the required time is approximately 270 months.
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