To add 9/4 and 2/8, we need to first find a common denominator:
9/4 = 18/8
Now we can add the two fractions:
18/8 + 2/8 = 20/8
Finally, we simplify the fraction by dividing the numerator and denominator by their greatest common factor, which is 4:
20/8 = 5/2
Therefore, 9/4 + 2/8 = 5/2.