=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