The contents are added with powder and then all the materials are mixed together.

Indonesians – please let me know what you’re trying to translate here!

Adding things

In English the simpler item is added to the more complex item:

• More marginal notes were added to later editions.
• NOT: Later editions were added with more marginal notes.
• Olive oil is added to almost every dish.
• NOT: Almost every dish is added with olive oil.
• Any finite number added to infinity is infinity.
• NOT: Infinity added with any finite number is infinity.
• New functionality was later added to the application.
• NOT: The application was later added with new functionality.
• A timeline has been added to this website.
• NOT: This website has been added with a timeline.

Conclusion

In our opening example, the powder is less complex than ‘the contents’, and so the following is more appropriate:

• Powder is added to the contents and then all the materials are mixed together.