Question

4. tính nhẩm

a. -23.101

b. 64-11

Answer 1

a,-23.101=-23.100-23=-2300-23=-2323

b,64.(-11)=64.(-10)-64=-640-64=-704

Answer 2

a.-23.101=(-23).100+(-23).1=-2323

b.64.(-11)=64.10+64.1=740.

Answer 3

a, -23 . 101 b, 64 - 11

= -23 . ( 100 + 1) = 64 . (-11)

= -23 . 100 + -23 .1 = 64 . -10 - 64 . 1

= -2300 + -23 = -640 - 64

= - 2323 = -704