About a third of an orange crop was ruined by a sudden frost. Another third of the undamaged fruit spoiled while being taken to market. How much of the original orange crop could the farmer sell at the produce market?

x -initial amount,

x/3 -damaged,
x - x/3 = 2x/3 - undamaged.
2x/(3•3) =2x/9 - spoiled
for sell
2x/3-2x/9 =4x/9