K-5 friendly lesson

One small step at a time.Read the idea, try the activity, and celebrate each win as you go.

Make the Number (Least Amount of Coins)

⚡️ Minimum Metal! You need to pay exactly 42 cents. But you don't want to carry 42 heavy pennies. What is the absolute smallest number of coins you can use?

Do this: Read the concept below, then try the quiz or activity.

Lesson 144 of 186

Concept

This is the ultimate puzzle game of money. Always start by using the BIGGEST coin possible.

🎯 The "Greedy Coin" Strategy: Target: 68 Cents. What is the least amount of coins to make 68c?

1. Be Greedy (Quarters/25): How many Quarters fit in 68? Two! (25, 50). 
   * Coins used: 2 (Quarters). Target left: 68 - 50 = 18c.
2. Next Biggest (Dimes/10): How many Dimes fit in 18? One! (10).
   * Coins used: 1 (Dime). Target left: 18 - 10 = 8c.
3. Next Biggest (Nickels/5): How many Nickels fit in 8? One! (5).
   * Coins used: 1 (Nickel). Target left: 8 - 5 = 3c.
4. The Scraps (Pennies/1): Use 3 Pennies.
   * Coins used: 3 (Pennies). 
5. Final Answer: 2 Quarters, 1 Dime, 1 Nickel, 3 Pennies. (Total: 7 coins to make exactly 68 cents!).

Try it

Minimum metal challenge!

Instructions: Make the exact amount of money using the absolute smallest number of coins possible. Use Quarters first!

Problem 1: Make 30 cents. * Start greedy: Can I use a Quarter? Yes! (1 Quarter = 25c). Leftover: 5c. * Which coin makes the last 5c perfectly? * Answer: ___ Quarter, ___ Nickel.

Problem 2: Make 41 cents. * Greedy 1: 1 Quarter (25c). Left over: 16c. * Greedy 2: 1 Dime (10c). Left over: 6c. * Greedy 3: 1 Nickel (5c). Left over: 1c. * Greedy 4: ___ Penny. * Answer: ___ Q, ___ D, ___ N, ___ P!

Problem 3: Make 51 cents. * (Hint: Quarter song! 25, 50! Two Quarters!). * Answer: ___ Q, ___ P.

Problem 4: Make 15 cents. * Answer: ___ D, ___ N.

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