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jonny [76]
3 years ago
14

A college some completed some courses worth 3 credits and some courses worth 4 credits. The students earned a total of 59 credit

s after completing 18 courses. How many courses worth 3 credits did the student complete?
Mathematics
1 answer:
Law Incorporation [45]3 years ago
3 0

The student completed 13 courses with 3 credit hours.

Step-by-step explanation:

Total credit hours = 59 credits hours

Total courses = 18

Let,

3 credit hours courses = x

4 credit hours courses = y

According to statement;

x+y=18     Eqn 1

3x+4y=59   Eqn 2

Multiplying Eqn 1 by 3

3(x+y=18)\\3x+3y=54\ \ \ Eqn\ 3

Subtracting Eqn 3 from Eqn 2

(3x+4y)-(3x+3y)=59-54\\3x+4y-3x-3y=5\\y=5

Putting y=5 in Eqn 1

x+5=18\\x=18-5\\x=13

The student completed 13 courses with 3 credit hours.

Keywords: linear equation, elimination method

Learn more about linear equations at:

  • brainly.com/question/12764620
  • brainly.com/question/12791734

#LearnwithBrainly

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Answer:

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Step-by-step explanation:

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In this problem, we have that:

Assume that weights of males are normally distributed with a mean of 170 lb, so \mu = 170

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