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Question
Using suitable identities, evaluate the following.
47 × 53
Evaluate
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Solution
We have,
47 × 53 = (50 – 3)(50 + 3)
= (50)2 – (3)2 ...[Using the identity, (a – b)(a + b) = a2 – b2]
= 2500 – 9
= 2491
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Chapter 7: Algebraic Expression, Identities and Factorisation - Exercise [Page 233]
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