3/8
625 / 1000 = 125 / 200 = 25 / 40 = 5 / 8 Five-eighths
0.4
39/8
.005
6/8 = 0.75
9⅝" (That is, if you meant how to write it out)
1/2 = 0.5
A banana is a non-fraction!
It looks like 2,500,000,000 : there is no need for a decimal point after the number.
78% of a fraction would look like this: 0.78, or on a calculator it could look like this: 77.5
Pretty simple. The answer is if you remember to look at ruler. 5/8 = 10/16= 20/32=40/64th