20:x=24: 12
24x=20* 12
24x/24=240/24
X= 10 Answer, it takes 10 hours to arrive.
2.6 class (1) teachers and students go camping ... (proportional) solution: it takes x hours.
15:3=27.5:x
x=27.5*3/ 15
x=5.5
3. 10m high telephone pole ... (inverse ratio) solution: let this tree be x meters.
1.5:x= 17.7/3
3x=47.2/ 17.7
x=8
4. The school sends the same car ... (inverse proportion)
Solution: suppose you want to send x cars.
105:5= 168:x
2 1= 168:x
x=8
5. Solution: Make X hours full. (proportional)
47.2:x= 17.7/3
3x=47.2/ 17.7
x=8
6. Direct proportion solution: suppose that X parts can be processed now.
12:8=x:200
8x= 12*200
8x/8=2400/8
x=300
Expansion: (126/14 * 2 * 7 = 9 * 2 * 7 =126 (yuan)
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The first big problem is to clarify right and wrong.
No matter how
The second big question is also seated accordingly.
32 12
Solution ratio: 6:1.1= x:13.2.
x=6* 13.2/ 1. 1
x=72
X: 12= 3/8 to 3/4.
X= 12* 3/8 * 3/4 (you can divide it here! )
x=6
4 inches x = 1.6 inches 0.8.
0.8x=4* 1.6
X=0.8 × (you can also make an appointment ~ ~)
x=8
x:0.75=0.6:0.5
0.5x=0.75*0.6
0.5 where x = 0.75 * 0.6 (about 0.75 and 0.5).
x=0.9
Well, I haven't done the remaining 37.38.39. This is our version. I don't know whether to adopt it or not.