Question

evaluate the following 4.15×3.85

Answer 1

Answer :-

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★ Method I

4.15 × 3.85

= 15.9775

★ Method II

4.15 × 3.85

= ( 4.00 + 0.15 ) ( 4.00 - 0.15 )

= ( 4.00 )² - ( 0.15 )² [ ★ Using identity ]

= 16 - 0.0225

= 15.9775

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★ Used identity - ( a² - b² ) = ( a + b ) ( a - b )

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Answer 2

4.15 * 3.85

= (4.00 + 0.15)(4.00 - 0.15)

Now apply (a + b) (a - b) = a^2 - b^2

= (4.00)^2 - (0.15)^2

= 16.0000 - 0.0225

= 15.9775


Thanks