A bag of mixed nuts contains cashews, pistachios, and almonds. There are 4000 total nuts in the bag, and there are 400 fewer almonds than pistachios. Cashews weigh 9, pistachios weigh 9, and almonds weigh 9. If the bag weighs 20.4 kg, find out how many of each type of nut are in the bag.

Cashews: