Respuesta :
The minimum average score Ethan can earn on his fifth and final test is option (D) 60% is the correct answer.
What is an average?
An average of a list of data is the expression of the central value(mean) of a set of data. Average is calculated by adding quantities together and dividing the total by the number of quantities.
For the given situation,
The scores for 4 exams are 68%,72%, 85%, and 90%.
Let the score for the fifth test be x.
Formula for the average,
[tex]A = \frac{Sum of individual scores}{Total number of tests}[/tex]
⇒ [tex]75=\frac{68+72+85+90+x}{5}[/tex]
⇒ [tex]375=315+x[/tex]
⇒ [tex]x=60[/tex]
Hence we can conclude that the minimum average score Ethan can earn on his fifth and final test is option (D) 60% is the correct answer.
Learn more about averages here
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