2.8/9 × 15/36 + 1/27
3. 12× 5/6 – 2/9 ×3
4.8× 5/4 + 1/4
5.6÷ 3/8 – 3/8 ÷6
6.4/7 × 5/9 + 3/7 × 5/9
7.5/2 -( 3/2 + 4/5 )
8.7/8 + ( 1/8 + 1/9 )
9.9 × 5/6 + 5/6
10.3/4 × 8/9 - 1/3
0. 12χ+ 1.8×0.9=7.2 (9-5χ)×0.3= 1.02 6.4χ-χ=28+4.4
1 1.7 × 5/49 + 3/ 14
12.6 ×( 1/2 + 2/3 )
13.8 × 4/5 + 8 × 1 1/5
14.3 1 × 5/6 – 5/6
15.9/7 - ( 2/7 – 10/2 1 )
16.5/9 × 18 – 14 × 2/7
17.4/5 × 25/ 16 + 2/3 × 3/4
18. 14 × 8/7 – 5/6 × 12/ 15
19. 17/32 – 3/4 × 9/24
20.3 × 2/9 + 1/3
2 1.5/7 × 3/25 + 3/7
22.3/ 14 ×× 2/3 + 1/6
23. 1/5 × 2/3 + 5/6
24.9/22 + 1/ 1 1 ÷ 1/2
25.5/3 × 1 1/5 + 4/3
26.45 × 2/3 + 1/3 × 15
27.7/ 19 + 12/ 19 × 5/6
28. 1/4 + 3/4 ÷ 2/3
29.8/7 × 2 1/ 16 + 1/2
30. 10 1 × 1/5 – 1/5 × 2 1
3 1.50+ 160÷40 (58+370)÷(64-45)
32. 120- 144÷ 18+35
33.347+45×2-4 160÷52
34(58+37)÷(64-9×5)
35.95÷(64-45)
36. 178- 145÷5×6+42 420+580-64×2 1÷28
37.8 12-700÷(9+3 1× 1 1) ( 136+64)×(65-345÷23)
38.85+ 14×( 14+208÷26)
39.(284+ 16)×(5 12-8208÷ 18)
40. 120-36×4÷ 18+35
4 1.(58+37)÷(64-9×5)
42.(6.8-6.8×0.55)÷8.5
43.0. 12× 4.8÷0. 12×4.8
44.(3.2× 1.5+2.5)÷ 1.6 (2)3.2×( 1.5+2.5)÷ 1.6
45.6- 1.6÷4= 5.38+7.85-5.37=
46.7.2÷0.8- 1.2×5= 6- 1. 19×3-0.43=
47.6.5×(4.8- 1.2×4)= 0.68× 1.9+0.32× 1.9
48. 10. 15- 10.75×0.4-5.7
49.5.8×(3.87-0. 13)+4.2×3.74
50.32.52-(6+9.728÷3.2)×2.5
The construction team dug ditches, and it was planned to dig 100 meters every day, and it was completed in 24 days, but it was actually completed 4 days ahead of schedule. How many meters does it actually dig every day?
100×24÷(24-4)
=2400÷20
= 120 (m)
2. A car traveled from A to B three hours ago 156 km. At this speed, it takes 8 hours to get from A to B. How many kilometers is there between A and B? (Use proportional solution)
156/3 :x/8
Solution: 3 x= 156×8
X=4 16
3. There are two ribbons, the first one is 6.2 meters long, and the second one is 0.2 meters shorter than the second one. How many meters are the two ribbons?
6.2+(6.2×2-0.2)
=6.2+ 12.2
= 18.4 (m)
4. A school uniform 54 yuan, in which the price of trousers is 4/5 of that of coat. What are the prices of coat and trousers?
X+4/5 X=54
9/5 X=54
X=30
30×4/5=24
5. To build a road, it takes four days for the first construction team and six days for the second construction team. If the two teams repair together, how many days can the road be completed?
1÷( 1/4+ 1/6)
= 1÷5/ 12
=2.4 (days)
6. On the map with the scale of1:4,000,000, the distance between A and B is 20 cm, and two trains start from A and B at the same time. The speed of A train is 55 kilometers per hour and that of B train is 45 kilometers per hour. They will meet in a few hours.
20/x: 1/4000000 8000000 cm =800 km
1x = 20×400000800(55+45)
X=80000000 =8 (hours)
7. A conical rice pile, with a bottom radius of 1 m and a height of 1.5 m, weighs about 600 kg per cubic meter of rice. How many kilograms does this study pile weigh?
1× 1×3. 14× 1.5× 1/3×600
=3. 14× 1.5× 1/3×600
=4.7 1× 1/3×600
= 1.57×600
=942 (kg)