What do i supposed to do with this please ?

Answer:
he has 26 1/6 square meters left.
Step-by-step explanation:
first, i divided 78 1/2 by 3, because he got 2 3rds done with only 1/3 left.
when i did that i got 26 1/6.
i highly recommend photmath app. it makes equations like that easy to put together and explain easily.