8,36,12(）

8,36,12(）

8:36=12:54

Choose four numbers from 5, 9, 12, 27 and 36 to form a proportion. What proportion can be formed?

As long as any four numbers can form a proportion, we can write eight proportion formulas
The four numbers that can form the formula are 9, 12, 27 and 36
The proportion formula can be written as follows:
Take 9 and 36 as internal terms (because 9 * 36 = 12 * 27) and 12 and 27 as internal terms
12：9=36:27 9:12=27:36
27:9=36：12 36:12=27:9
12:36=9:27 9:27=12:36
27:36=9:12 36:27=12:9
If you encounter such a problem, first select four numbers, and then make their products equal. The numbers in the formula of equal products can be divided into two groups. One side of the equal sign is the first group, and the other side is the second group. In this way, let the two numbers in each group be the same terms (one number is the internal term, and the other number is the introvert). Remember this trick, and you can easily write out eight proportional expressions

1. Is it OK to use two ratios of 3: (3:1, 9:3, 18:6, 36:12)?
2. The ratio of energy to 1.2:3 is (4:10), (40:100). Is that ok
Can 120:3 160:4 form a ratio? If so, please write the ratio
4. Write out the two ratios whose ratio is 1 and make up the ratio ()

1. Yes
2. Yes
3. It can be 120:3 = 160:4
4. 1：1=2：2

0.75 = fraction 15 = fraction 36 = fraction 15 divided by fraction

75 = 15 of 20 = 27 of 36 = 15 divided by 20