Missing number
- Select the number that will replace the question mark (?) in the following table.6420853993? Answer: B. 72 Answer: (B) 72 Third number = difference of the squares: 6² - 4² = 20 , 8² - 5² = 39 . So 9² - 3² = 81 - 9 = 72 . 1
- If 2 → 6, 3 → 24 and 4 → 60, then 5 → ? Answer: A. 120 Answer: (A) 120 Rule: n³ - n . 8 - 2 = 6 , 27 - 3 = 24 , 64 - 4 = 60 . So 125 - 5 = 120 . 1
- Select the number that will replace the question mark (?) in the following table.5323643475? Answer: A. 47 Answer: (A) 47 Third number = product + sum of the first two: 5 × 3 + 5 + 3 = 23 , 6 × 4 + 6 + 4 = 34 . So 7 × 5 + 7 + 5 = 47... 1
- If 2 → 9, 4 → 65 and 5 → 126, then 3 → ? Answer: D. 28 Answer: (D) 28 Rule: n³ + 1 . 2³ + 1 = 9 , 4³ + 1 = 65 , 5³ + 1 = 126 . So 3³ + 1 = 28 . 1
- Select the number that will replace the question mark (?).(5, 4, 21), (6, 3, 19), (7, 5, ?) Answer: D. 36 Answer: (D) 36 Third number = product of the first two + 1: 5 × 4 + 1 = 21 , 6 × 3 + 1 = 19 . So 7 × 5 + 1 = 36 . 1
- Select the number that will replace the question mark (?).(4, 5, 41), (6, 2, 40), (3, 7, ?) Answer: A. 58 Answer: (A) 58 Third number = sum of squares of the first two: 4² + 5² = 41 , 6² + 2² = 40 . So 3² + 7² = 9 + 49 = 58 . 1