3
Review: money and puzzles
Joyful Mathematics: Chapters 8–13
GoalReview coins, notes, spending and solving riddles.
New words
rupee · money in India, ₹price · how much a thing costsclue · a hint in a riddle
Explanation
Coins are ₹1, ₹2, ₹5 and ₹10. Notes are ₹10, ₹20, ₹50 and ₹100. Add the values to find the amount. To find change, take the price away from what you have. In a riddle, use every clue and check your answer.
Worked examples
₹5 and ₹10 make ₹15.
A ball costs ₹8. You have ₹10. ₹2 is left.
I am 1 less than 70. I am 69.
Class activity
Shop and riddle. Set a price for three things at home, such as ₹4, ₹7 and ₹9. Ask a family member to pay with paper coins. Check the total by adding. Then end with a number riddle for each person.
Practice
1
How much money is this?
₹17.
2
A cup costs ₹6. You have ₹10. How much is left?
₹4.
3
Two coins make ₹12. Which coins are they?
₹10 and ₹2.
4
I have 4 tens and 6 ones. Who am I?
46
5
Which is the odd one out?
The kite.