We don't need to worry about the "5" part, yet
1) Take 228 and subtract the non-repeating part of the decimal = 228- 22 = 206....this is our numerator
2) In the denominator, write the same number of 9's as the repeating part of the decimal= 9
And write the same number of 0's as the non-repeating part of the decimal = 00
So .228 (8 repeating) = 206 / 900 = 103 / 450
So we have
5 + 103 / 450 = 2343 / 450
Here is another method :
x = 5.228
100x = 522.8888.....
1000x = 5228.8888.....
1000x - 100x = 900x = 5228.8888.... - 522.8888.... = 4706
900x = 4706
x = 4706/900 simplify as needed (= 5 103/450)