GRE考试

【单选题】

Which of the followingCANNOT be expressed as the sum of three consecutive integersA、18

B、
B、24
C、28
D、33
E、36

网考网参考答案：C
网考网解析：
The sum of three consecutive integers can be expressed as n+(n+1)+(n+2)=3n+3=3(n+1), and so must be a multiple of 3. Only 28, Choice C, is not a multiple of 3. **Quickly add up sets of three consecutive integers: 4 + 5 + 6 = 15, 5 + 6 + 7 = 18, 6 + 7 + 8 = 21, and so on, and see the pattern (they’re all multiples of 3); or cross off the choices as you come to them. document.getElementById("warp").style.display="none"; document.getElementById("content").style.display="block"; 查看试题解析出处>>