2. 14÷( 1-2/5)= 70/3m 70/3x 3/7 = 10m。

3.45×( 1- 1/5)=36 trees.

4.4000 ÷ (1+1/9) = 3600 vehicles.

5.5+3 = 8 96 ÷ 2 = 48m 48× 5/8 = 30m

48×3/8 = 16m 30× 16 = 480 m2

6.1.168 ÷ (1-3/4) = 672 trees 2.168× (1+3/4) = 294 trees 3./kloc-

7. 1260× ( 1+4/2 1) = 1500 1500× ( 1+3/25) = 1680.

8.146 ÷ 2 = 73 73× 3 = 219m

9.57.6 Don't know?

10.4× 70 = 280m3 400-280 =120m3120 ÷ (7-4) = 40 times.

11.2× 3.14×10 = 62.8m.

12.8-1.72 = 6.28m 6.28m 4 =1.72m1.72m 3.14 = 0.5m.

13. 12÷2 = 6m 3. 14×6×6 = 1 13.04 m2。

14.64÷8 = 8cm 8÷2 = 4cm 3. 14x4x 4 = 50.24 cm2。

15.8000×3×2.89%=693.6 yuan

16.5000× 2× 2.43%+5000 = 5243 yuan

17.3000-2000 =1000 yuan 1000×20%=200 yuan 200+ 1000 yuan = 1200 yuan.

18.225+25 = 2.5 million yuan (250-225)÷250= 10%

19.120×1/5 = 24 people.

20.24 One fifth of a meter × 5/11=1meter 1 1×24 One fifth of a meter =266.2 square meters.

Hehe, I hope it works for you.