1/5单选题
难度：
1.学校把学生学科的期中、期末两次成绩分别按40%、60%的比例计入学期学科总成绩. 小明期中数学成绩是85分，期末数学总成绩是90分，那么他的学期数学成绩（ ）
| A | 85分 |
| B | 87.5分 |
| C | 88分 |
| D | 90分 |
- 提示1：
- IOWtpuacn+aVsOWtpuaIkOe7qT3mnJ/kuK3mlbDlrabmiJDnu6nDl+aJgOWNoOeahOeZvuWIhuavlCvmnJ/mnKvmlbDlrabmiJDnu6nDl+aJgOWNoOeahOeZvuWIhuavlA==
正确答案：Qw==
PGRpdj7op6PvvJrlsI/kuq7ov5nlrabmnJ/mgLvor4TmiJDnu6k9ODXDlzQwJSs5MMOXNjAlPTg4PC9kaXY+
2/5单选题
难度：
2.
已知
的平均数为a，
的平均数为b，则
的平均数为（ ）
| A |
|
| B |
|
| C |
|
| D |
|
- 提示1：
- PHA+6K6h566X5Ye6IDxpbWcgc3JjPSJodHRwczovL3AyLnFpbmdndW8uY29tL0cxL00wMC8yMy80Qy9yQkFDRTFNTVZPN1RSZERhQUFBQnlSVnEzX2syNzYucG5nIiBkYXRhLWNrZS1zYXZlZC1zcmM9Imh0dHBzOi8vcDIucWluZ2d1by5jb20vRzEvTTAwLzIzLzRDL3JCQUNFMU1NVk83VFJkRGFBQUFCeVJWcTNfazI3Ni5wbmciIGhlaWdodD0iMjEiIHdpZHRoPSI5MCI+55qE5ZKM77yM6Zmk5LulMjA8L3A+
正确答案：QQ==
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
3/5单选题
难度：
3.若3，4，5，6，a，b，c的平均数是12，则a，b，c的平均数是（ ）
| A | 12 |
| B | 22 |
| C | 33 |
| D | 66 |
- 提示1：
- IOW5s+Wdh+aVsOaYr+aMh+WcqOS4gOe7hOaVsOaNruS4reaJgOacieaVsOaNruS5i+WSjOWGjemZpOS7peaVsOaNrueahOS4quaVsA==
正确答案：Qg==
PGRpdj7op6PvvJrnlLHpopjmhI/nn6XvvIzvvIgzKzQrNSs2K2ErYitj77yJw7c3PTEy77yMPC9kaXY+PGRpdj7iiLRhK2IrYz02NiA8L2Rpdj48ZGl2PjY2w7czPTIyPC9kaXY+
4/5单选题
难度：
4.
已知a，b，c的平均数是m，那么3a+5，3b+5，3c+5的平均数是（ ）
| A | m |
| B | 3m |
| C | 3m+5 |
| D | 不能确定 |
- 提示1：
- PHA+5bmz5Z2H5pWw5piv5oyH5Zyo5LiA57uE5pWw5o2u5Lit5omA5pyJ5pWw5o2u5LmL5ZKM5YaN6Zmk5Lul5pWw5o2u55qE5Liq5pWwPC9wPg==
正确答案：Qw==
PGRpdj7op6PvvJph77yMYu+8jGPnmoTlubPlnYfmlbDmmK9t77yM6YKj5LmIM2ErNe+8jDNiKzXvvIwzYys155qE5bmz5Z2H5pWw5pivM20rNTwvZGl2Pg==
5/5单选题
难度：
5.小明参加数学考试，前两次的平均分是85分，后三次的总分是270分，求小明这五次考试的平均分数是（ ）
| A | 88 |
| B | 80 |
| C | 85 |
| D | 90 |
- 提示1：
- IOmmluWFiOaxguWHuuWJjeS4pOasoeeahOaAu+WIhu+8jOWGjeWKoOS4iuWQjuS4ieasoeeahOaAu+WIhu+8jOeUqDXmrKHnmoTmgLvmiJDnu6nDtzXljbPlj6/msYLlh7rkupTmrKHogIPor5XnmoTlubPlnYfliIbmlbA=
正确答案：QQ==
PGRpdj7op6PvvJrvvIg4NcOXMisyNzDvvInDtzU9ODg8L2Rpdj4=