To sum more than two numbers quickly, follow these easy steps:

1. Don't sum the numbers pairwise.
2. Stack the numbers vertically, and align them to the right.
3. Compute the sum of each column of digits, starting from the right.
4. Proceed until you reach the last digit of the longest number.

That's it!

Historians speculate that the symbol + came to represent the addition as the result of a lengthy modification of the Latin conjunction et. The introduction of the symbol + for addition is relatively recent, dating back to the 14th century. Before that, different symbols were used, including p̅ and the bidirectional glyph used by Egyptians.

45,200. To calculate the sum of 41,381 and 3,819:

1. Stack the numbers aligned to the right.

2. Sum the rightmost numbers: 9 + 1 = 10. Save 0 and lend 1 to the digits to the left.

3. Sum 8 and 1 and add the 1 from the step before: 8 + 1 + 1 = 10. Save 0 and carry the one.

4. Sum 3, 8, and the 1 from step 3.: 8 + 3 + 1 = 12. Save 2 and carry 1.

5. Sum 1, 3, and the 1 from above: 1 + 3 + 1 = 5.

6. Build the result: 45,200.