<PRE><B>Question 1195414</B>
A = P (1 + rt)
A	=	final amount
P	=	initial principal balance
r	=	annual interest rate
t	=	time (in years)

Given:
A = 7200 investment to double in value
P = 3600 
r = 6.3% = 0.063
t = ?

Substitute

7200 = 3600 ( 1 + .063t) Divide both sides by 3600)
2 =  1 + .063t Subtract 1 both sides
1 = 0 + .063t
1 = .063t divide both sides by .063
1/.063 = t 

t = 15.873015873015873015873015873016
Round your answer to the nearest tenth.
t = 15.9 years



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