GMAT考试

【单选题】If the average (arithmetic mean) of x and y is 40, and z-x=60, what is the average of y and z
A、20
B、50
C、65
D、70
E、140

网考网参考答案：D
网考网解析：
To get the average of y and z, you need to find half of the sum of y+ z. To obtain that number, first restate the first statement as an equation: x+y=80. Add that equation to z-x=60, so that x+y+z-x=80+60=y+z=140. The average of y and z is 140/2=70. document.getElementById("warp").style.display="none"; document.getElementById("content").style.display="block"; 查看试题解析出处>>