Modules Daily Challenge Dashboard
📅 2026-03-11

Daily Math Challenge

📚 Science ⭐ Hard 🎓 Grade 6-8
The half-life of a substance is 10 days. If you start with 800 grams, how much remains after 20 days?
Answer
200 grams

📝 Step-by-Step Solution

1
Start: 800 g
2
After 10 days: 800 ÷ 2 = 400 g
3
After 20 days: 400 ÷ 2 = 200 g
💡 Helpful Hints
• Half-life means divide by 2 each period
• 20 days = 2 half-lives