1. Using 1 / 3, 2 / 5, 25 and 30 as the four items of proportion, how many proportions can you form? Please write out what you can do 2. How many ratios can be made up of 4, 3, 6 and 8? Write them out separately

Question 1: 1.30:25 = 2 / 5:1 / 3
2.25:30=1/3:2/5
3.30:2/5=25:1/3
4.2/5:30=1/3:25
Question 2: 1.4:3 = 8:6
2.3:4=6:8
3.4:8=3:6
4.8:4=6:3
(because 4:3 = 8:6 And 8:6 = 4:3 are the same meaning, so I didn't list them. These are the main ones.)

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