计算(能简算的要简算). 8×99+3.8 57-55÷56-1/56.
问题描述:
计算(能简算的要简算).
8×99+3.8
57-55÷56-
. 1 56
答
(1)8×99+3.8
=8×(100-1)+3.8
=8×100-8+3.8
=800-8+3.8
=795.8;
(2)57-55÷56-
1 56
=57-55×
-1 56
1 56
=57-(55×
+1 56
)1 56
=57-(55+1)×
1 56
=57-56×
1 56
=57-1
=56.