Twenty Five, 20+5, and (2x10)+(5x1).
20/25 equals 0.8
It is: 20/25 times 100/1 = 80%
80
25/100 25cents
0.25 n
20%, 0.2, 1/5
20 + 5 = 25
2 to the power of 20 is written as: 220
In word forms, you can write it as 20 billion dollars, twenty billion dollars, $20 billion. Or you can write it as $20,000,000,000. There are at least 4 ways to write it, and probably more.
You can write 0.2 like 20% or 1/5.
20/25 = 4/5 in its lowest terms and 4 divided by 5 = 0.8