Answer:
a. the investment earns 4%
b. yes
Step-by-step explanation:
The "rule of 72" says that an investment earning compound interest at x% will double in value after 72/x years. That is, ...
f(x) = 72/x
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<h3>a.</h3>
We interpret f(4) to mean Becky's friend is interested in the doubling time for an investment that earns 4% interest.
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<h3>b.</h3>
Using the above formula, ...
f(4) = 72/4 = 18
The friend's math is correct.
Well it would be 70% of them because Jack had 100% and 30% minus 100% is 70%
Answer:
z = 0
Step-by-step explanation:
3 (z + 7) = 21
3z + 21 = 21
3z = 0
z = 0
Answer:
-77
Step-by-step explanation:
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