Question
1. What is \( 39 * 41 \)?
2. What is \( 44 * 57 \)?
3. What is \( 898 * 9 \)?
4. Can you estimate the square root of 183?
2. What is \( 44 * 57 \)?
3. What is \( 898 * 9 \)?
4. Can you estimate the square root of 183?
Check your answer
Solution
Answer: 1599, 2508, 8082, approximately 13.5
1. \( 39 * 41 = (40 - 1)(40 + 1) = 1600 - 1 = 1599 \)
2. \( 44 * 57 = 44 * (60 - 3) = 2640 - 132 = 2508 \)
3. \( 898 * 9 = 900 * 9 - 2 * 9 = 8100 - 18 = 8082 \)
4. \( 13^2 = 169, 14^2 = 196 \), and 183 is close to the midpoint, so \( \sqrt{183} \approx 13.5 \).
2. \( 44 * 57 = 44 * (60 - 3) = 2640 - 132 = 2508 \)
3. \( 898 * 9 = 900 * 9 - 2 * 9 = 8100 - 18 = 8082 \)
4. \( 13^2 = 169, 14^2 = 196 \), and 183 is close to the midpoint, so \( \sqrt{183} \approx 13.5 \).