Respuesta :

Answer:

[tex]t=14.2\ years[/tex]    

Step-by-step explanation:

we know that    

The compound interest formula is equal to  

[tex]A=P(1+\frac{r}{n})^{nt}[/tex]  

where  

A is the Final Investment Value  

P is the Principal amount of money to be invested  

r is the rate of interest  in decimal

t is Number of Time Periods  

n is the number of times interest is compounded per year

in this problem we have  

[tex]t=?\ years\\ P=\$500,000\\ r=0.05\\n=1\\ A=\$1,000,000[/tex]  

substitute in the formula above  and solve for t

[tex]1,000,000=500,000(1+\frac{0.05}{1})^{(1)t}[/tex]

[tex]2=(1.05})^{t}[/tex]  

Apply log both sides

[tex]log(2)=log[(1.05})^{t}][/tex]  

[tex]log(2)=(t)log(1.05)[/tex]  

[tex]t=log(2)/log(1.05)[/tex]  

[tex]t=14.2\ years[/tex]          

Answer:

~14.2066 years

Step-by-step explanation:

assuming p.a. means per annual:

$500,000 with intrest rate 5% per year. how many years for money to become $1,000,000?

with annual intrest, a percentage of the money you invest is added to your balance every year

set up equation: (original money*(1+ intrest rate))^x=goal money

there is a 1 because you are adding on to the original (100%) amount of money

x is the number of years untill goal money. is an exponent because it depends on the previous years balance. note that amount of money gained will change per year.

50,000*(1+0.05)^x=1,000,000

solve------

divide by 50,000 both sides

1*(1+0.05)^x=2

(1+0.05)^x=2

(1.05)^x=2

apply log_1.05 to both sides

log_1.05 (1.05)^x= log_1.05  2

x= log_1.05  2

use calculator to approx

~14.2067 years

hope this helps

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