Problema Solution

Caitlyn needs to earn a B in her geology class. Her current test scores are 78,93,79, and 82. Her final exam is worth 4 test scores. In order to earn a B Caitlyn's average must lie between 80 and 89 inclusive. What range of scores can Caitlyn receive on the final exam to earn a B in the course?

Answer provided by our tutors

let x = the score on the final exam


the average is: (78 + 93 + 79 + 82 + 4x)/(4 + 4)


the average must lie between 80 and 89 inclusive:


80 <= (78 + 93 + 79 + 82 + 4x)/(4 + 4)


by solving we find:


x >= 77


click here to see the step by step solution of the inequality:


Click to see all the steps



(78 + 93 + 79 + 82 + 4x)/(4 + 4) <= 89


by solving we find:


x <= 95


click here to see the step by step solution of the inequality:


Click to see all the steps



the range of scores that Caitlyn can receive on the final exam to earn a B in the course is between 77 and 95 inclusive.