I did the problem myself and my teacher always said thatif you don't get the exact answer then round to the closest one. The answer that i got was 31,808.6, the closest one to that would be letter C.
Josh is incorrect, he did not examine the expression correctly, therefore his answer was wrong.
Put in a equality
20 > (70/x)
then you solve
20x > 70
x>70/20
x> 3.5 you can not put part of a chair in a row so you round up
****You can put 4 or more chairs in a row****
20% of 3km is 0.6 Kilometer
