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3 years ago

John's grades in Algebra are: 65, 83, and 93. What grade does John need on the final exam to get an 85

Mathematics

1 answer:

hoa [83]3 years ago

8 0

Answer:

99 marks

Step-by-step explanation:

Let 'x' be the mark in final exam

Sum of all the data's/ Number of data's = Mean

$\frac{65+83+93+x}{4}=85\\\\\\\frac{241+x}{4} = 85$

241 + x = 85*4

241 + x = 340

x = 340 - 241

x = 99

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beks73 [17]

Delete as this is the wrong answer. Made a typo in the answer.

Answer:

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Step-by-step explanation:

-3x - 8y = 20 .... (1)

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What we can do is take the (2) equation

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