Question

小学方程、简便运算.简便运算：7.2÷0.4-7.2×0.4 55.55×55+45.45×55-55方程：4x-2（1

Answer 1

7.2÷0.4-7.2×0.4=18-2.88

=15.12

55.55×55+45.45×55-55

=55x(55.55+45.45-1)

=55x100

=5500

4x-2（100-x）=40

4x-200+2x=40

6x=200+40

x=40