Add the total number of rolls that were greater than 3.
This would be the number 4, 5 and 6.
8 + 11 + 10 = 29 rolls higher than 3.
Now divide the number of rolls higher than 3 by the total number of rolls which is given as 50:
29 / 50 = 0.58
Multiply by 100 to get the percent:
0.58 x 100 = 58% of the rolls were higher than 3.