Jincy opened her piggy bank. She found 8 coins of ₹1, 9 coins of ₹2 and 5 coins of ₹5. She wants to buy stickers worth ₹38. What possible combination of coins can she use to pay the exact amount?
Given:
- 8 coins of ₹1 (total ₹8)
- 9 coins of ₹2 (total ₹18)
- 5 coins of ₹5 (total ₹25)
- Amount needed: ₹38
Step 1: Calculate total value of each coin type: ₹1 coins: 8 × ₹1 = ₹8 ₹2 coins: 9 × ₹2 = ₹18 ₹5 coins: 5 × ₹5 = ₹25 Total available = ₹51
Possible Combinations to make ₹38:
Combination 1: 4 × ₹5 + 9 × ₹2 = ₹20 + ₹18 = ₹38
Combination 2: 5 × ₹5 + 6 × ₹2 + 1 × ₹1 = ₹25 + ₹12 + ₹1 = ₹38
Combination 3: 3 × ₹5 + 9 × ₹2 + 5 × ₹1 = ₹15 + ₹18 + ₹5 = ₹38
Explanation
The chapter presents a real-world problem requiring students to find combinations of coins that add up to exactly ₹38. Students need to explore different combinations using the available coins: 8 coins of ₹1 (total ₹8), 9 coins of ₹2 (total ₹18), and 5 coins of ₹5 (total ₹25).
Solution Steps
Step 1: Calculate total value of each coin type: ₹1 coins: 8×₹1=₹8, ₹2 coins: 9×₹2=₹18, ₹5 coins: 5×₹5=₹25
Step 2: Find combinations that sum to ₹38
Step 3: Combination 1: 4×₹5 + 9×₹2 = ₹20 + ₹18 = ₹38
Step 4: Combination 2: 5×₹5 + 6×₹2 + 1×₹1 = ₹25 + ₹12 + ₹1 = ₹38
Step 5: Combination 3: 3×₹5 + 9×₹2 + 5×₹1 = ₹15 + ₹18 + ₹5 = ₹38