Ray's New Primary Arithmetic · Lesson LXXV · Unit 7: Signs, bigger numbers and mixed problems
75. Buying, selling and paying in goods
Goal: Your child works out gain, and what is still owed when part is paid in goods.
You'll need
- Coins and small items to "sell"
- A slate, small whiteboard or paper and pencil
What's in the book
Problems such as "A drover bought 10 sheep, at 3 dollars a head, and sold them for 5 dollars a head: how much did he gain?"
The lesson, step by step
What is gain?
Explain gain (profit): sold for more than you paid. Gain = selling price less cost.
Play it
Your child "buys" 3 toys at 2 cents and sells them at 5 cents. How much gain?
Work through the page
Do the problems.
Afterwards
Talk about how a lemonade stand makes (or doesn't make) a gain.
Answers to the book's problems
1. Charles 4, Henry 16. 2. 3 cents. 3. 23 cents. 4. 10 cents. 5. 9 cents; 3 cents each. 6. 6 cents. 7. 7 flags, 49 cents. 8. 45 cents. 9. 35 cents. 10. 50 cents. 11. 10 cents. 12. 48 cents. 13. 20 dollars.
Worked out for this site from the scan. If a number in your copy differs, trust the book.