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2 years ago

15

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?

1 answer:

Oxana [17]2 years ago

5 0

Answer:

76

Step-by-step 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.

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Step-by-step explanation:

Hi there!

We want to find the distance between the points (2, -2) and (-4, 7).

To do that, we can use the distance formula.

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