问题
填空题
简便方法计算:
(1)1998+998+98=
(2)43+40+39+41+37+42=
答案
(1)1998+998+98,
=2000+1000+100-6,
=3100-6,
=3094;
(2)43+40+39+41+37+42,
=(43+37)+(39+41)+(40+42),
=80+80+82,
=242.
简便方法计算:
(1)1998+998+98=
(2)43+40+39+41+37+42=
(1)1998+998+98,
=2000+1000+100-6,
=3100-6,
=3094;
(2)43+40+39+41+37+42,
=(43+37)+(39+41)+(40+42),
=80+80+82,
=242.