Answer:
Tyrell has completed a greater fraction of his problems,
but Brandon completed a greater number of problems.
Explanation:
Brandon:
23/50
Tyrell:
15/27 = 5/9
The LCD of 50 and 9 is 450
23/50 = 207/450
5/9 = 250/450
Since 250/450 > 207/450, then 15/27 > 23/50
Tyrell has completed a greater fraction of his problems.
Since 23 > 15, Brandon has completed a greater number of problems.