SAT试题类型 Mathematics > Standard Multiple Choice

Read the following SAT test question and then click on a button to select your answer.

The sum of the digits of a three-digit number is 12. If the hundreds digit is 3 times the tens digit and the tens digit is 1 over 2 the units digit, what is the tens digit of the number?
Answer Choices

(A) 2
(B) 3
(C) 4
(D) 6
(E) 9

答案:A

解析:

Explanation

If x stands for the tens digit, then 3 times x stands for the hundreds digit and 2 times x stands for the units digit. Since the sum of the digits is 12, (3 times x) + x + (2 times x) = 12. Solving this gives x = 2.