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Evaluate using suitable identitiie. 49...

Evaluate using suitable identitiie.
`497 xx 505`

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To evaluate \( 497 \times 505 \) using suitable identities, we can use the identity for the product of two numbers in the form of \( (a - b)(a + b) = a^2 - b^2 \). ### Step-by-Step Solution: 1. **Rewrite the Numbers**: We can express \( 497 \) and \( 505 \) in terms of \( 500 \): \[ 497 = 500 - 3 \quad \text{and} \quad 505 = 500 + 5 \] 2. **Apply the Identity**: Now, we can use the identity: \[ (a - b)(a + b) = a^2 - b^2 \] Here, let \( a = 500 \), \( b = 3 \) and \( c = 5 \). We will calculate: \[ 497 \times 505 = (500 - 3)(500 + 5) \] 3. **Expand the Expression**: Using the distributive property: \[ (500 - 3)(500 + 5) = 500 \times 500 + 500 \times 5 - 3 \times 500 - 3 \times 5 \] 4. **Calculate Each Term**: - \( 500 \times 500 = 250000 \) - \( 500 \times 5 = 2500 \) - \( -3 \times 500 = -1500 \) - \( -3 \times 5 = -15 \) 5. **Combine the Results**: Now, we combine all these results: \[ 250000 + 2500 - 1500 - 15 \] 6. **Perform the Addition and Subtraction**: - First, add \( 250000 + 2500 = 252500 \) - Then, subtract \( 1500 \): \( 252500 - 1500 = 251000 \) - Finally, subtract \( 15 \): \( 251000 - 15 = 250985 \) Thus, the final answer is: \[ \boxed{250985} \]
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