Question 1207702: In your Economics 101 class,you have scores of 68, 82, 87, and 89 on the first four of five tests. To get a grade of B, the average of the first five test scores must be greater than or equal to 80 and less than 90. (a) Solve an inequality to find the range of the score that you need on the last test to get a B. (b) What score do you need if the fifth test counts double?
Answer by mananth(16946) (Show Source):
You can put this solution on YOUR website! In your Economics 101 class,you have scores of 68, 82, 87, and 89 on the first four of five tests. To get a grade of B, the average of the first five test scores must be greater than or equal to 80 and less than 90. (a) Solve an inequality to find the range of the score that you need on the last test to get a B. (b) What score do you need if the fifth test counts double?--+
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You have scores of 68, 82, 87, and 89 on the first four of five tests
the average of the first five test scores must be greater than or equal to 80 and less than 90.
To equal average 80 let x be the socre in 5th test
80 =(68+ 82+87+ 89+x)/5
400 = 68+ 82+87+ 89+x
400=326+x
x= 400-326=74
To equal average 90 let x be the socre in 5th test
90 =(68+ 82+87+ 89+x)/5
450 = 68+ 82+87+ 89+x
450=326+x
x = 124
To get a B , you need to score between 74 and 123 (inclusive) on the last test.
For (b) value is double method is same
For double value instead of x take 2x
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