Simplify the following using the rules for identities :
(i) $28 \times 32$
(ii) $102 \times 98$

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Solution

(i) $28 \times 32 = 28 \times (30 + 2)$

$= 840 + 56$

$= 896$

(ii) $102 \times 98 = 102 \times (100 - 2)$

$= 102 \times 100 - 102 \times 2$

$= 10200 - 204$

$= 9996$

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Simplify the following using the rules for identities :(i) 28×32(ii) 102×98

(i) 28×32=28×(30+2) =840+56 =896 (ii) 102×98=102×(100−2) =102×100−102×2 =10200−204 =9996

Simplify the following using the rules for identities :
(i) $28 \times 32$
(ii) $102 \times 98$

(i) $28 \times 32 = 28 \times (30 + 2)$

$= 840 + 56$

$= 896$

(ii) $102 \times 98 = 102 \times (100 - 2)$

$= 102 \times 100 - 102 \times 2$

$= 10200 - 204$

$= 9996$