A person invest $300 in an account that earns 3.45%annual interest compounded quarterly.Find when the value of the investment reaches $700.If necessary round to the nearest tenth

Respuesta :

Answer:

It will take a time of 24.65 year.

Step-by-step explanation:

The principal amount invested by person ( P ) = $300.

The annual rate of interest ( r ) = 3.45 %.

The amount or future value ( A ) = $700.

We have to find the time ( t ) when his future value becomes $700.

Given that interest compounded quarterly, n = 4.

Now using the compound interest formula,

A = P * [tex](1 + \frac{r}{n} )^{n*t}[/tex]

[tex]700 = 300 * ( 1 + \frac{0.0345}{4} )^{4 * t}[/tex]

2.3333 = [tex]( 1 + \frac{0.0345}{4} )^{4 * t}[/tex]

Taking log both sides.

[tex]log2.333 = log ( 1 + \frac{0.0345}{4} )^{4 * t}[/tex]

0.3679 = (4 * t ) * log 1.008625

0.3679 = 4 * t * 0.003729

t = 24.65 year.

Answer: it will take 24.6 years

Step-by-step explanation:

We would apply the formula for determining compound interest which is expressed as

A = P(1+r/n)^nt

Where

A = total amount in the account at the end of t years

r represents the interest rate.

n represents the periodic interval at which it was compounded.

P represents the principal or initial amount deposited

From the information given,

A = 700

P = 300

r = 3.45% = 3.45/100 = 0.0345

n = 4 because it was compounded 4 times in a year.

t = 6 months = 6/12 = 0.5 year

Therefore,.

700 = 300(1 + 0.0345/4)^4 × t

700/300 = (1 + 0.008625)^4t

2.33 = (1.008625)^4t

Taking log of both sides,

Log 2.33 = 4t × og 1.008625

0.367 = 0.0149t

t = 0.367/0.0149

t = 24.6 years