= 16×(77+23)
= 16× 100
= 1600
(2)28×30+30×22
=30×(28+22)
=30×50
= 1500
(3)32×27+ 18×27
=27×(32+ 18)
=27×50
= 1350
(4) 125×64
= 125×8×8
= 1000×8
=8000
(5)76× 10 1
=76×( 100+ 1)
=76× 100+76× 1
=7600+76
=7676
(6)695- 134+ 105- 166
=(695+ 105)-( 134+ 166)
=800-300
=500
definition
Addition: the operation of combining two numbers into one number.
Subtraction: when two addends and one of them are known, the operation of finding the other addend.
Multiplication: the operation of finding the product of two numbers.
Division: the operation of finding another factor by knowing the product of two factors and one of them.