The Rule of 70 is a way to estimate the number of years it takes for an investment to double in value by dividing 70 by the annual interest rate.
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For the first asset (10% interest): \[ \text{Doubling Time} = \frac{70}{10} = 7 \text{ years} \] After 14 years (which is 2 doubling periods), the amount will double twice: \[ \text{Value} = 10,000 \times 2 \times 2 = 40,000 \]
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For the second asset (5% interest): \[ \text{Doubling Time} = \frac{70}{5} = 14 \text{ years} \] After 14 years, the amount will double once: \[ \text{Value} = 10,000 \times 2 = 20,000 \]
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Calculating the difference: \[ \text{Difference in Value} = \text{Value of First Asset} - \text{Value of Second Asset} = 40,000 - 20,000 = 20,000 \]
Thus, the approximate difference in the value of the two assets after 14 years is:
a. $20,000