1, calculate the following ratios: 1 / 3:1 / 7 = () 90g: 0.6kg () 2, simplify the following ratios: 3.5:25 = () 3. Dissolve 25 grams of salt into 200 grams of water. The simplest weight ratio of salt to brine is () 4. If the ratio of two numbers is 1 / 4, and the former and latter terms of the ratio are expanded four times at the same time, then the ratio is equal to () 5,3 percentage points is (), 0.5 has () 1%

1, calculate the following ratios: 1 / 3:1 / 7 = () 90g: 0.6kg () 2, simplify the following ratios: 3.5:25 = () 3. Dissolve 25 grams of salt into 200 grams of water. The simplest weight ratio of salt to brine is () 4. If the ratio of two numbers is 1 / 4, and the former and latter terms of the ratio are expanded four times at the same time, then the ratio is equal to () 5,3 percentage points is (), 0.5 has () 1%

1. 1/3:1/7=7/21:3/21=7:3
90g:0.6kg=90g:600g=3:20
2. 3.5:25=35:250=7:50
3. Mass of brine = mass of Salt + mass of water = 225g
Mass of salt: mass of brine = 25g: 225g = 1:9
4. 4
5. 3% 0.5=50%=50*1%