Question

Jose wants to have an average of 80 for his 4 exams. Each exam is scored on a scale of 0 to 100. His first three exam scores are: 87, 72, 85. What does Jose need to score on the 4th exam to have a mean of 80 on all 4 exams?

Answer 1

76

Explanation:

Assuming that all exams have the same weight, in order to achieve an average score of 80, the sum of all scores must equal 4 x 80. Therefore, the grade Jose needs in his last exam is:

`87+72+85+x=4*80\\x=76`

Jose needs to score a 76 in his last exam to have a mean of 80.