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The smallest number that must be subtracted from 796 to make it a perfect square is:
A{'text': '8'}
B{'text': '12'}
C{'text': '10'}
D{'text': '14'}
Answer & Solution
Correct answer: B. {'text': '12'}
1. Find the largest perfect square ≤ 796.
2. 28² = 784 and 29² = 841.
3. So 784 is the largest perfect square ≤ 796.
4. The number to subtract is 796 − 784 = 12.
5. Hence the answer is **12**.
_Source: Selina Concise ICSE Class 8 Mathematics Ch 3 "Squares and Square Roots", Perfect square adjustments_
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