Answer:
x = 5
Step-by-step explanation:
5 x's
6+6=12 so if there is 239 people in the first 6 rows, the other six rows also has the same amount of people. So you add 239+239 and you got your answer, 478 people are in the first 12 rows
I solved it on paper so it's easier.
But good luck ! :)