1.7+3.98+,
=1.7+(3.98+0.02),
=1.7+4,
=5.7;
×51,
=×(50+1),
=×50+×1,
=47+,
=47;
5.73-3+(4.27-2),
=5.73+4.27-(3+2),
=10-6,
=4;
45×2.08+1.5×37.6,
=1.5×62.4+1.5×37.6,
=1.5×(62.4+37.6),
=1.5×100,
=150;
99999×77778+33333×66666,
=99999×77778+33333×(3×22222),
=99999×77778+(33333×3)×22222,
=99999×77778+99999×22222,
=99999×(77778+22222),
=99999×100000,
=9999900000;
,
=(362+548×361)÷(362×548-186),
=[362+548×(362-1)]÷(362×548-186),
=[362-548+548×362]÷(362×548-186),
=(362×548-186)÷(362×548-186),
=1;
+++…+,
=×[(1-)+(-)+(-)+…+(-)],
=×,
=;
++++,
=(1-)+(-)+(-)+(-)+(-),
=1-+-+-+-+-,
=1-,
=;