I'll solve this step by step, working through each question to find the 4 sums (2 addition and 2 subtraction) using the three numbers given.
Let me work through each question:
Q1 is already completed as an example:
Numbers: 5, 15, 10
- Sum 1: 10 + 5 = 15 ✓
- Sum 2: 5 + 10 = 15 ✓
- Sum 3: 15 - 5 = 10 ✓
- Sum 4: 15 - 10 = 5 ✓
Q2: Numbers are 12, 8, 4
I need to find which two numbers add up to the third number.
- Check: 8 + 4 = 12 ✓
- So the addition facts are: 8 + 4 = 12 and 4 + 8 = 12
- The subtraction facts are: 12 - 8 = 4 and 12 - 4 = 8
Q3: Numbers are 8, 9, 17
Check which two add to make the third:
- 8 + 9 = 17 ✓
- Addition facts: 8 + 9 = 17 and 9 + 8 = 17
- Subtraction facts: 17 - 8 = 9 and 17 - 9 = 8
Q4: Numbers are 90, 30, 60
Check which two add to make the third:
- 30 + 60 = 90 ✓
- Addition facts: 30 + 60 = 90 and 60 + 30 = 90
- Subtraction facts: 90 - 30 = 60 and 90 - 60 = 30
Q5: Numbers are 3, 9, 6
Check which two add to make the third:
- 3 + 6 = 9 ✓
- Addition facts: 3 + 6 = 9 and 6 + 3 = 9
- Subtraction facts: 9 - 3 = 6 and 9 - 6 = 3
Q6: Numbers are 18, 30, 12
Check which two add to make the third:
- 18 + 12 = 30 ✓
- Addition facts: 18 + 12 = 30 and 12 + 18 = 30
- Subtraction facts: 30 - 18 = 12 and 30 - 12 = 18
Let me verify all my calculations:
- Q2: 8+4=12 ✓, 12-8=4 ✓, 12-4=8 ✓
- Q3: 8+9=17 ✓, 17-8=9 ✓, 17-9=8 ✓
- Q4: 30+60=90 ✓, 90-30=60 ✓, 90-60=30 ✓
- Q5: 3+6=9 ✓, 9-3=6 ✓, 9-6=3 ✓
- Q6: 18+12=30 ✓, 30-18=12 ✓, 30-12=18 ✓
All calculations check out!
Final Answer:
Q2 (12, 8, 4):
Sum 1: 8 + 4 = 12
Sum 2: 4 + 8 = 12
Sum 3: 12 - 8 = 4
Sum 4: 12 - 4 = 8
Q3 (8, 9, 17):
Sum 1: 8 + 9 = 17
Sum 2: 9 + 8 = 17
Sum 3: 17 - 8 = 9
Sum 4: 17 - 9 = 8
Q4 (90, 30, 60):
Sum 1: 30 + 60 = 90
Sum 2: 60 + 30 = 90
Sum 3: 90 - 30 = 60
Sum 4: 90 - 60 = 30
Q5 (3, 9, 6):
Sum 1: 3 + 6 = 9
Sum 2: 6 + 3 = 9
Sum 3: 9 - 3 = 6
Sum 4: 9 - 6 = 3
Q6 (18, 30, 12):
Sum 1: 18 + 12 = 30
Sum 2: 12 + 18 = 30
Sum 3: 30 - 18 = 12
Sum 4: 30 - 12 = 18
Parent Tip: Review the logic above to help your child master the concept of inverse operations questions.
