Chris buys $$1$$ durian, $$2$$ pineapples and $$3$$ watermelons using $$$440$$. Dylan buys $$4$$ durians, $$6$$ pineapples and $$9$$ watermelons using $$$1625$$. How much does $$1$$ durian cost? 
Overseas Competition->Knowledge Point->Calculation Modules->Comparing, Ordering and Estimating