GRE考试

【单选题】

Sandrine is now 5 times as old as Nicholas, but 7 years from now, she will be 3 times as old as he will be then. How old is Sandrine nowA、15

B、
B、20
C、21
D、25
E、35

网考网参考答案：E
网考网解析：
Set up a table. Time Nicholas Sandrine Now x 5x In 7 years x+7 5x+7 Then 5x + 7 = 3(x + 7) 5x + 7 = 3x + 21 2x=14 x=7. Sandrine, therefore, is 35. **Use TACTIC 1, Chapter 11, but since Sandrine is 5 times as old as Nicholas, avoid Choice C, the only answer that is not a multi-ple of 5. Try Choice B, 20. Then Nicholas is 4. In 7 years, he’ll be 11 and Sandrine will be 27, which is less than 3 times as old. Try a larger number: 25 or 35. document.getElementById("warp").style.display="none"; document.getElementById("content").style.display="block"; 查看试题解析出处>>