MTC MTC Mental Math Strategies 2 — Questions and Answers
Question 1: Using the 'add one more group' strategy, what is 6 × 9 if you know 6 × 8 = 48?
- 54 (Correct answer)
- 48
- 60
- 56
Correct answer: 54
6 × 8 = 48, and adding one more group of 6 gives 48 + 6 = 54.
Question 2: Using the near-ten strategy, what is 11 × 8?
- 88 (Correct answer)
- 80
- 96
- 98
Correct answer: 88
10 × 8 = 80, and 80 + 8 = 88, so 11 × 8 = 88.
Question 3: If 7 × 7 = 49, what is 7 × 8 using the 'add one more group' strategy?
- 56 (Correct answer)
- 49
- 63
- 54
Correct answer: 56
7 × 7 = 49, and 49 + 7 = 56, so 7 × 8 = 56.
Question 4: Using the near-ten strategy (10 × n − n), what is 9 × 9?
- 81 (Correct answer)
- 72
- 90
- 80
Correct answer: 81
10 × 9 = 90, and 90 − 9 = 81, so 9 × 9 = 81.
Question 5: Using doubling twice, what is 8 × 8? (Start with 2 × 8 = 16)
- 64 (Correct answer)
- 56
- 72
- 48
Correct answer: 64
2 × 8 = 16 → 4 × 8 = 32 → 8 × 8 = 64 by doubling twice.
Question 6: Using the near-ten strategy, what is 9 × 12?
- 108 (Correct answer)
- 99
- 117
- 120
Correct answer: 108
10 × 12 = 120, and 120 − 12 = 108, so 9 × 12 = 108.
MTC MTC Mental Math Strategies 2
Using the 'add one more group' strategy, what is 6 × 9 if you know 6 × 8 = 48?