Question 37
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For how many two-digit numbers is the sum of the number and the number formed by reversing its digits a perfect square?
- A 9
- B 7
- C 4
- D 8 Correct
Correct Answer: Option D
Number + reverse = 11(a + b)
For 11(a + b) to be a perfect square, a + b must be 11 (a + b ≤ 18)
Two-digit numbers with digit sum 11: 29, 38, 47, 56, 65, 74, 83, 92
Count = 8
Answer: 8
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