Homework said 'find five ways to make 20'. She wrote 10 + 10 five times

Her school is IB, so maths homework is mostly these open questions. Last night's was 'find five ways to make 20'. She wrote 10 + 10, five times, very neatly, and was quite proud of herself 🙂 I laughed, and then didn't know what to do. If I say 'try different numbers' I'm more or less handing her the answer. If I leave it, her teacher gets five identical lines. How do you nudge without doing it for them? Or do I send it in as it is and let the teacher take it from there