The "rule of 72" says that the doubling time in years is approximately 72 divided by the interest rate in percent. To make the money grow by a factor of 4 requires that it double twice, so will take twice as long as the period to double once.
2×72/11.3 ≈ 12.7 . . . . years
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The "rule of 72" is an approximation. The actual quadrupling time for this interest rate and compounding is about 12.6 years. (The actual product of doubling time and nominal interest rate is about 71.25.)
Answer: x=37.8, you can solve by writing a proportion
For a hyperbola

where

the directrix is the line

and the focus is at (0, c).
Here, we have c = 5, a² = 9, so b² = 5² - 9 = 16.
a = √9 = 3
b = √16 = 4
Your hyperbola's constants are ...
a = 3
b = 4
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Please note that the equation of a hyperbola has a negative sign for one of the terms. The equation given in your problem statement is that of an ellipse.
Sorry but there is no question
<span>16.45 is less than 16.454. The reason is because 16.454 is 4 thousandths more than 16.45 assuming that both numbers are exact numbers. Although it is only a small amount it still makes 16.45 less than 16.454.</span>