In each row, the third number follows the same rule from the first two. Row 1: 5, 3, 22. Row 2: 6, 4, 32. Row 3: 7, 5, ?. What is the missing number?
Answer and explanation
Correct answer: A. 44
- Step 1: Row 1: 5² - 3 = 25 - 3 = 22. Step 2. Row 2: 6² - 4 = 36 - 4 = 32, so the rule is first² - second. Step 3. Row 3: 7² - 5 = 49 - 5 = 44. Answer: 44. Why not the others: 12: This is 7 + 5, which does not match the rule in row 1. 30: This is 5² + 5, which uses the wrong number in the rule. 49: This is 7², which leaves out the subtraction.
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