=66×2 1+ 19×2 1+85×(2 1-2)
=66×2 1+ 19×2 1+85×2 1-85×2
=(66+ 19+85)×2 1-85×2
= 160×2 1- 170
=3 190
(2)36× 1 1 1+888×8
=36× 1 1 1+ 1 1 1×(8×8)
=36× 1 1 1+ 1 1 1×64
= 1 1 1×(64+36)
= 1 1 100
(3)99×99+ 199
=99×( 100- 1)+ 199
=9900-99+ 199
=9900+( 199-99)
= 10000