2. 职称英语
  3. Ellen has received the following scores on 3 exams: 82, 74, and 90. What score w

Ellen has received the following scores on 3 exams: 82, 74, and 90. What score w

游客2024-01-12  50
问题 Ellen has received the following scores on 3 exams: 82, 74, and 90. What score will Ellen need to receive on the next exam so that the average(arithmetic mean)score for the 4 exams will be 85?
选项
答案 94
解析 Let x represent the score on Ellens next exam. This initial step of assigning a variable to the quantity that is sought is an important beginning to solving the problem. Then in terms of x, the average of the 4 exams is

which is supposed to equal 85. Now simplify the expression and set it equal to 85:

Solving the resulting linear equation for x, you get
246 + x = 340
x = 94
Therefore, Ellen will need to attain a score of 94 on the next exam.
转载请注明原文地址:http://tihaiku.com/zcyy/3355424.html
相关试题推荐
随机试题
最新回复(0)