美国学术能力评估考试（SAT）
单选题If 70% of the bananas in a particular harvest had an average (arithmetic mean) length of 7 inches and 30% of the bananas in that harvest had an average (arithmetic mean) length of 5 inches, what was the average (arithmetic mean) length, in inches, of a
题目
6.0
6.2
6.4
6.6
6.8
相似问题和答案
第1题：
In a weather report GMT stands for ________ ．
A.Greenwich Mean Time
B.Local Mean Time
C.General Cargo
D.General Average
第2题：
The average height of the surface of the sea for all stages of the tide over a 19 year period is called ______.
A.mean high water
B.mean low water
C.half-tide level
D.mean sea level
第3题：
The centerline of a standard "Shewhart' control chart represents:
A . the process target
B . the nominal dimension specified by the customer
C . the nominal dimension specified by the designer
D . the true process average or mean
E . the process sample average or mean
第4题：
n+5
n+6
n+7
n+8
n+9
最小的整数为n。它们是连续的奇数。这组整数为:n,n+ 2, n+4, n+6, n+8, n+10, n+12, n+14。计算这些整数的平均数即为将它们想加除于8。得出（8n+56）/8=n+7
第5题：
（1）条件告诉了Kara学校学生学习时间的总标准差，无法计算Kara的学习时间数值；（2）条件指出Kara的学习时间距离平均数有两个标准差区间，不能确定其是高于还是低于平均值，故本题应选E项。
第6题：
The height of a light is measured from which reference plane?
A.Mean low water
B.Mean high water
C.Average water level
D.Geographical sea level
第7题：
How is the size of chain determined?______.
A.Length of link in inches
B.Diameter of metal in link in inches or centimeters
C.Links per fathom
D.Weight of stud cable in pounds
如何测定锚链的大小？用英寸或厘米表示金属链环的直径
第8题：
187 The centerline of a standard "Shewhart' control chart represents:
A. the process target
B. the nominal dimension specified by the customer
C. the nominal dimension specified by the designer
D. the true process average or mean
E. the process sample average or mean
第9题：
6
10
12
18
20
根据题目中已知的数量关系，可列等式如下：c+d= 12×2=24……①；c+d+e=10×3=30……②。把等式①代入等式②得，24+e=30，e=6。
第10题：
由10a+10b=35可得10(a+b)=35→a+b=3.5，所以a和b的平均数是3.5÷2=1.75。