John earns 33.33% more than Peter. By what percentage is Peter's earning less than that of John's?

Let's solve the problem step by step.

1. Let's assume Peter's earnings are $P$.

2. John earns 33.33% more than Peter. Therefore, John's earnings can be calculated as: $J = P + 0.3333P = 1.3333P$

3. We need to find by what percentage Peter's earnings are less than John's. To do this, we calculate the difference between John's and Peter's earnings: $\text{Difference} = J - P = 1.3333P - P = 0.3333P$

4. To find the percentage by which Peter's earnings are less than John's, we use the formula: $\text{Percentage} = \left( \frac{\text{Difference}}{J} \right) \times 100$

5. Substituting the values we have: $\text{Percentage} = \left( \frac{0.3333P}{1.3333P} \right) \times 100$

6. Simplifying the fraction: $\text{Percentage} = \left( \frac{0.3333}{1.3333} \right) \times 100$

7. Calculating the division: $\text{Percentage} = 0.25 \times 100$

8. Finally: $\text{Percentage} = 25\%$

So, Peter's earnings are 25% less than John's.