1. **State the problem:** We need to calculate the difference between 1951.6 and 63.7. 2. **Write the subtraction expression:** $$1951.6 - 63.7$$ 3. **Perform the subtraction:** Subtract the decimal parts first: $0.6 - 0.7$ is not possible without borrowing, so borrow 1 from the integer part. $$1951.6 = 1950 + 1.6$$ Borrowing 1 from 1951 gives: $$1950 + (1.6) = 1950 + (1 + 0.6) = 1950 + 1 + 0.6$$ So, subtracting 63.7: $$1951.6 - 63.7 = (1950 + 1.6) - 63.7 = 1950 - 63 + (1.6 - 0.7)$$ Calculate each part: $$1950 - 63 = 1887$$ $$1.6 - 0.7 = 0.9$$ 4. **Add the results:** $$1887 + 0.9 = 1887.9$$ 5. **Final answer:** $$\boxed{1887.9}$$