Home › CBSE Class 8 › Mathematics › Squares and Square Roots › Compute 105² without direct multiplication:
Compute 105² without direct multiplication:
A10025
B10525
C11025
D11225
Answer & Solution
Correct answer: C. 11025
105² = (100 + 5)² = 100² + 2·100·5 + 5² = 10000 + 1000 + 25 = 11025. Alternatively, using the (a5)² rule: a = 10, a(a+1) = 10·11 = 110, so 105² = 11000 + 25 = 11025.
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