Question 15 of 21intermediate✨ CreateShort Answer4 marks

Make cards with numbers 0-5. Make two 3-digit numbers using these cards. Add the two numbers and subtract the two numbers. Rearrange the cards and try to get a bigger sum. Rearrange the cards and try to get a smaller difference. Check with your friends who has got the biggest sum and smallest difference.

Correct Answer

Given: Cards with numbers 0, 1, 2, 3, 4, 5

For Biggest Sum: Use the largest digits in the highest place values. Place 5 and 4 in the hundreds place, 3 and 2 in the tens place, and 1 and 0 in the ones place. Example: 531 + 420 = 951

For Smallest Difference: Make the two numbers as close in value as possible. Use 3 and 2 in the hundreds place, and arrange the remaining digits so the larger number is as small as possible and the smaller number is as large as possible. Example: 301 - 254 = 47

Key Insight: Placing larger digits in higher place values (hundreds, then tens) gives larger sums. For smallest difference, the two numbers should be close in value, which means their hundreds digits should be consecutive, and the remaining digits should be arranged to minimize the larger number and maximize the smaller number.

Exercise: Card Activity (Page 15) | Q: 9 | (Page Page 15)
For More Understanding

Explanation

This activity teaches place value concepts. For the biggest sum, students should use the largest available digits in the highest place values (5 and 4 in hundreds, 3 and 2 in tens, 1 and 0 in ones) to get a sum of 951. For the smallest difference, students should arrange numbers so they are close in value, using consecutive hundreds digits (3 and 2) and placing the smallest remaining digits in the larger number and the largest remaining digits in the smaller number to get a difference of 47.

Solution Steps

  1. Step 1: Available digits: 0, 1, 2, 3, 4, 5

  2. Step 2: For biggest sum: Use largest digits in highest places (5 and 4 in hundreds, 3 and 2 in tens, 1 and 0 in ones)

  3. Step 3: Example: 531 + 420 = 951 (biggest sum)

  4. Step 4: For smallest difference: Make numbers close in value by using consecutive hundreds digits (3 and 2)

  5. Step 5: Make the larger number as small as possible (301) and the smaller number as large as possible (254)

  6. Step 6: Example: 301 - 254 = 47 (smallest difference)

  7. Step 7: Compare with friends to find the best arrangements

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