2, 90- 12×5=30
3. 1687÷7+29=270 cases
4.400× 7+660 = 3460m
5,80 ÷ 2× 3 =120m
6. 10×7-2=68 years old
7.400×4- 120 = 1480m 1480-400 = 1080m。
8. 130+85- 158=57 copies
9. 1200-236-402=562 sets.
10,8× 2+8 = 24 people
1 1, 100+40+ 100=240 yuan.
12,42× 3-42 = 84 people,
13,200-40+200 = 360 yuan 360 < 390, so I can't buy it.
14,210+25+210 = 435 Completed task 435+20-400=55.
15, 18÷6×8=24 yuan
16,2× 4× 23 =184 yuan.
17,24× 7 ÷ 6 = 28 bottles
18,40 ÷ 2 ÷ 4 = 5 boxes
19, (158+ 16)×3=522 yuan.
20, (1 1-3)×7=56 km.
2 1, 27×3×4=324 flowers
22,62 ÷ 2× 3 = 93 yuan
23, (48- 12)× 10=360 yuan.
24, (420+50)×6=2820 yuan
25,42 ÷ 2× 7 =147 yuan
26, 134×2×5= 1340.