Shannon scored 89, 78, and 93 on three exams this semester. There is one exam remaining. What score does she need to achieve on the last exam to have an overall mean of 90 on her exams.

98

90

100

96

Question

Shannon scored 89, 78, and 93 on three exams this semester. There is one exam remaining. What score does she need to achieve on the last exam to have an overall mean of 90 on her exams.
		
98
		
90
		
100
		
96

isaiah.feynman · Answer

Let that score be x. We know that the mean of the four exams would be |dw:1389901056368:dw| He need to get a 100 to have such an average.