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Please help me!!!!!!!!!!

Please help me!!!!!!!!!!-example-1

1 Answer

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Answer:

3.0 years

Explanation:

The value of a certain account (in dollars) after t years is given by the equation:


B = 300 * 1.3^t

To determine how long it will take for the value of the account to increase to $660, substitute B = 660 into the given equation and solve for t:


300 * 1.3^t=660

Divide both sides of the equation by 300:


(300 * 1.3^t)/(300)=(660)/(300)


1.3^t=2.2

Take natural logs of both sides of the equation:


\ln(1.3^t)=\ln(2.2)

Apply the log power rule:


t\ln(1.3)=\ln(2.2)

Divide both sides of the equation by ln(1.3):


(t\ln(1.3))/(\ln(1.3))=(\ln(2.2))/(\ln(1.3))


t=(\ln(2.2))/(\ln(1.3))


t=3.0052010397...


t=3.0\; \sf (1\;d.p.)

Therefore, it will take 3.0 years for the account value to increase to $660.

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