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tekilochka [14]
3 years ago
6

On three examinations, you have grades of 85, 78, and 84. There is still a final examination, which counts as one grade In order

to get an A your average must be at least 90. If you get 100 on the final, what is your numerical average? 86.75 (Type an integer or a decimal.) Is an A in the course possible? Yes No To eam a B in the course, you must have a final average of at least 80 What grade must you got on the final to earn a B in the course? Type an integer or a decimal) Enter your answer in the answer box and then click Check Answer All parts showing Clear All Pearson Copyright © 2019 Pearson Education Inc. All rights reserved. Terms of Use Privacy
Mathematics
1 answer:
Greeley [361]3 years ago
6 0

Answer:

  • It's not possible to earn an A in the course
  • I must have a 73 or MORE to earn a B in the course

Step-by-step explanation:

The average obtained at the end of the course will be:

\frac{85+78+84+x}{4} = av

Where x is the grade obtained in the final examination and av is the final average. To obtain an A, av has to be at least 90, av≥90, and to obtain an B, av has to be at least 80, av≥80

  • Is an A in the course possible?

So, if we get 100 on the final average:

x = 100,

av = (85+78+84+100)/4 = 86,75 and  86,75∠90.

<em>Answer: No, the higher grade obtained would be 86,75.</em>

  • What grade you must have in the final to earn a B in the course

To earn a B, av≥80:

av= \frac{85+78+84+x}{4 \ }\geq  80\\ \frac{247+x}{4}\geq80   \\247+x\geq 80*4\\ x\geq 320-247\\ x\geq 73

<em>Answer: I must have a 73 or MORE to earn a B in the course</em>

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Step-by-step explanation:

<u><em>The complete question is</em></u>

Part 1) The volume of the pyramid shown in the figure is 9,15,21, or 63 cubic centimeters?. Part 2) If the slant height of the pyramid increases by 4 centimeters and its height increases by 2 centimeters, the volume of the pyramid increases by 6,9,12 or 21 cubic centimeters?

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see the attached figure to better understand the problem

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