MTC MTC Mental Math Strategies 1 — Questions and Answers
Question 1: Using the doubling strategy, what is 4 × 8? (Start with 2 × 8 = 16, then double)
- 32 (Correct answer)
- 24
- 40
- 28
Correct answer: 32
2 × 8 = 16, and 16 doubled = 32, so 4 × 8 = 32.
Question 2: Using the doubling strategy, what is 8 × 6? (Start with 4 × 6 = 24, then double)
- 48 (Correct answer)
- 42
- 56
- 40
Correct answer: 48
4 × 6 = 24, and 24 doubled = 48, so 8 × 6 = 48.
Question 3: Using the 'multiply by 10 then halve' strategy, what is 5 × 8?
- 40 (Correct answer)
- 45
- 35
- 50
Correct answer: 40
10 × 8 = 80, and 80 ÷ 2 = 40, so 5 × 8 = 40.
Question 4: Using the near-ten strategy, what is 9 × 7? (Use 10 × 7 first)
- 63 (Correct answer)
- 70
- 56
- 54
Correct answer: 63
10 × 7 = 70, and 70 − 7 = 63, so 9 × 7 = 63.
Question 5: Using the doubling strategy, what is 12 × 7? (Start with 6 × 7 = 42, then double)
- 84 (Correct answer)
- 77
- 91
- 72
Correct answer: 84
6 × 7 = 42, and 42 doubled = 84, so 12 × 7 = 84.
Question 6: Using the near-ten strategy, what is 9 × 11?
- 99 (Correct answer)
- 110
- 88
- 100
Correct answer: 99
10 × 11 = 110, and 110 − 11 = 99, so 9 × 11 = 99.
MTC MTC Mental Math Strategies 1
Using the doubling strategy, what is 4 × 8? (Start with 2 × 8 = 16, then double)