for how long do we have to invest R$3005 at a rate of 36% per year to abstain R$3000 in interest?

Given the formula for simple interest:

1. Identify the principal, interest rate, and interest:

P = 3005

r = 0.36

I = 3000

2. Substitute these values into the formula:

t = \frac{I}{P \cdot r}

3. Calculate the time:

t = \frac{3000}{3005 \cdot 0.36}

4. Compute the result:

t\approx2.77\text{ years}

So, the answer is t\approx2.77\text{ years}