vedic math
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The factors of the sum equal the sum of the factors

Gunakasamuchchayah

This sutra provides a quick way to verify multiplication using digit sums. By reducing each factor and the product to their single-digit sums, you can instantly check whether a multiplication result is correct without redoing the full calculation.

How It Works

  1. 1.Find the digit sum of the first factor by adding its digits repeatedly until you get a single digit.
  2. 2.Find the digit sum of the second factor the same way.
  3. 3.Multiply these two digit sums and reduce the result to a single digit.
  4. 4.Find the digit sum of the claimed product.
  5. 5.If the digit sums match, the answer is very likely correct. If they don't match, it's definitely wrong.

Examples

Verify 23 × 14 = 322
Step 1 / 6

Verify: 23 × 14 = 322. Find the digit sum of each factor.

2323
1414
Claimed product322

Try It Yourself

37 × 24

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