The fourth number is ()
One or one in 16 or one in 25, all three will do
What's the ratio of 0.8 2.5 9 / 20 with 1 number
8:9 of 20 = 40 of 9:2.5
Add two seventh, 20 and 3 to a number to form a proportion ()
2/7:20=3:210