Add and Subtract Multi-Digit Numbers Study the example showing subtraction of multi-digit numbers. Then solve problems 1-5. Example A total solar eclipse was visible from Oregon to South Carolina on August 21, 2017 The last one seen in the contiguous United States had been in 1979. How many years apart were these two events? Subtract the years. Regroup as needed. The two events were 38 years apart. Write a related problem that could be solved using the calculation below. Then solve it and show all regrouping. Calculation: 2017 38 Problem:​