1. **State the problem:** Simplify the expression $1.400 + 1400 + 1400 + 1400$. 2. **Rewrite the numbers:** Note that $1.400$ is the same as $1.4$ (one point four), but since the other numbers are $1400$, it is likely a decimal point confusion. Assuming $1.400$ means $1400$ (one thousand four hundred), the expression becomes $1400 + 1400 + 1400 + 1400$. 3. **Add the numbers:** Since all four terms are $1400$, add them: $$1400 + 1400 + 1400 + 1400 = 4 \times 1400 = 5600$$ 4. **Final answer:** The simplified sum is $5600$.