Question

Find the product using suitable properties.

(a) 738 × 103

(b) 854 × 102

(c) 258 × 1008

(d) 1005 × 168

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Answer 1

$\huge\underline\mathrm{SOLUTION:-}$

(a) Given 783 × 103

= 783 × (100 + 3)

= 783 × 100 + 783 × 3

• (using distributive property)

= 78300 + 2214

= 76014

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(b) Given 854 × 102

= 854 × (100 + 2)

= 854 × 100 + 854 × 2

• (using distributive property)

= 85400 + 1708

= 87108

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(c) Given 258 × 1008

= 258 × (1000 + 8)

= 258 × 1000 + 258 × 8

• (using distributive property)

= 258000 + 2064

= 260064

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(d) Given 1005 × 168

= (1000 + 5) × 168

= 1000 × 168 + 5 × 168

• (using distributive property)

= 168000 + 840

= 168840

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