Answer:
-33.3%
Explanation:
The percentage loss is the same for 2 crates as for 1 crate.
% loss = (loss/cost) · 100%
% loss = (N100 -N150)/(N150) · 100% = -1/3 · 100% ≈ -33.3%
The percentage loss is 33.3%.
_____
Additional comment
In the above, the minus sign indicates a percentage change that is a loss. If the sign were positive, it would indicate a percentage profit.