Welcome to your interview.
The question is on your right: Single-Measurement Coin Bag. Take a moment with it first.
Talk your thinking through with me if you like - when you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes). Discussion and graded submissions share your five interviewer interactions, so spend them well.
You have 10 bags of coins. Nine bags contain genuine coins weighing 10 grams each, and one bag contains counterfeit coins weighing 9 grams each. Using a spring scale only once, how can you identify the bag with the counterfeit coins?