Skylar’s grades on four math tests are 85, 78, 77, and 69. What does Skylar need to score on the next test in order to have a mean score of

Question

Skylar’s grades on four math tests are 85, 78, 77, and 69. What does Skylar need to score on the next test in order to have a mean score of 80?

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Calantha 6 months 2021-07-27T11:20:13+00:00 2 Answers 11 views 0

Answers ( )

  1. kimcuc
    0
    2021-07-27T11:21:33+00:00
    Reply

    It is given that,

    The mean is the average of 5 numbers.

    Then if the,

    Next score is x the mean will be.

    We can solve now,

    → (85 +78 +77 + 69 + x)/5 = 80

    → (309 + x)/5 = 80

    → 309 + x = 80 × 5

    → 309 + x = 400

    → x = 400 – 309

    → x = 91

    Hence, the next score is 91.

  2. Delwyn
    0
    2021-07-27T11:21:48+00:00
    Reply

    Answer:

    • 91

    Step-by-step explanation:

    The mean the the average of 5 numbers. If the next score is x, then the mean is:

    • (85 + 78 + 77 + 69 + x)/5 = 80

    Solve it for x:

    • 309 + x = 80*5
    • x = 400 – 309
    • x = 91

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