• [x] Time speed
• [x] Distance
• [x] Trains
• [x] Boats and streams
• [x] Profit loss
• [x] Discount Percentage
• [x] Simple interest
• [x] Compound interest
• [x] Average
• [x] Age
• [x] Time and work
• [ ] Pipes and cisterns
• [ ] Ratio and proportion
• [ ] Permutations and combination
• [x] Clocks
• [ ] Calendars
• [x] Allegations and mixture