Arnulfo deposited $55 into a savings account for which interest is compounded semiannually. according to the rule of 72, what interest rate will cause his money to double in approximately 23 years?

3.13%

Step-by-step explanation:

We have been given that Arnulfo deposited $55 into a savings account for which interest is compounded semiannually.

The rule of 72 states that to find the number of years needed to double our money at a given interest rate, we just divide 72 by the interest rate (r).

, where r represents the interest rate.

As we have been given that it will take approximately 23 years to double Arnulfo's money, so we can set an equation as:

Let us solve for r .

Therefore, at a interest rate of 3.13% Arnulfo's money will be doubled in approximately 23 years.

6 cm

step-by-step explanation:

2, 2, 2 or -4, 20, 29

step-by-step explanation:

there is two ways you can do it.