The tens digit of a two-digit number is two more than its unit digit. The two-digit number is 7 times the sum of the digits. Find the units digits?
Correct answer: B. 2
- A. 1
- B. 2
- C. 3
- D. 4
- E. None of these
Explanation
Let the units digit be u, so the tens digit is u + 2. The number is 10(u + 2) + u = 11u + 20, while seven times the digit sum is 7(2u + 2) = 14u + 14; equating them gives u = 2. A likely choice is option c, 3, from applying the seven-times condition to the number without first forming the sum of its digits.
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