Square root distributes over multiplication: 225×64=225×64=15×8=120 (check: 1202=14400=225×64). The trap 23 adds the roots, which would only be valid if roots distributed over addition — they do not. The trap 289 is 225 + 64, and 14400 is the product before the root is taken.
Answer: D) 120
Key idea: Square root by long division
Use this for larger numbers (or non-perfect squares).
**Step 1**: Pair the digits from the right (e.g. 1849 → 18 49). **Step 2**: Find the largest integer whose square ≤ first pair. Write it as the first quotient digit. Subtract its square. **Step 3**: Bring down the next pair. Double the current quotient — that's your divisor's prefix. Find a digit d such that (prefix × 10+d)×d ≤ current dividend. **Step 4**: Append d to quotient, subtract, repeat.
Example: 1849=43.(42=16 ≤ 18; remainder 2; bring down 49 → 249; double 4 = 8; find d where (80+d)d ≤ 249; d=3 gives 83×3=249.) Quotient = 43.
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