let number of green balls= x
let number of orange balls=x+4
x+x+4=38
2x=38-4
2x=34
x=17
number of green balls=17
number of orange balls=21
N=1.2 I don't know what you are asking in the second part of the question
0.51
The hundredths place increases when it is higher than or equal to 5 in the thousandths place.