综合套题十
80 ÷ 1000 =	32 ×25 =	6.5 ÷ 100 =
450 - 70 =	8000 ÷ 50 =	21.5 × 10 =
22 +199 =	71.7 + 81.9 =	5.5 - 3.8 =
80 - 7.39 =	8.72 × 1000 =	8.4 + 2.16 =
2、简便计算
99 × 161 + 161	664 - 142 - 158	18 × 1009
52 × 125 × 8	8000 ÷ 8 ÷ 125	321 + 164 + 279 + 393 + 236
3、四则运算与灵活运用
(83 × 3 + 989) × 7	7.05 - 5.2 + 6.88	25 × 64
262 ÷ 50 × 25	98 × 521	665 ÷ 19 ÷ 5 + 426
5×[(175-49)÷9+190]	125 × 56 × 25	603 - ( 403 - 473 )