35 x 34 + 35 x 86 + 65 x 75 + 65 x 45
= 35 × ( 34 + 86 ) + 65 × ( 75 +45 )
= 35×120+65×120
= 120 × ( 35 + 65 )
= 120 × 100
= 12000
3 x 25 x 8 + 4 x 37 x 6 + 2 x 38 x 12
= 24 × 25 + 24 × 37 + 24 × 38
= 24 × ( 25 + 37 + 38 )
= 24 × 100
= 2400
12 x 53 + 53 x 172 - 53 x 84
= 53 × ( 12 + 172 - 84 )
= 53 ×100
= 5300