What is the Square Root of 400?

Instant answer with step-by-step solution

√400 = 20
√400 = 20
✓ 400 is a perfect square

Step-by-step explanation

  1. We need to find √400 — a number that when multiplied by itself equals 400.
  2. Check: is 400 a perfect square? Yes — because 20 × 20 = 400.
  3. Therefore √400 = 20
  4. Verification: 20² = 20 × 20 = 400 ✓
  5. 400 is a perfect square. Its square root is a whole number.

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