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fiasKO [112]
3 years ago
15

Tim and Jim are working on a school project together. If he had to work by himself, it would take

Mathematics
1 answer:
Vladimir [108]3 years ago
4 0

Answer: 6 hours

Step-by-step explanation:

Given, Tim and Jim are working on a school project together.

Tim takes 10 hours to complete the school project.

If Jim worked alone, it would take him 15 hours

Let t be the time they both take if they work together.

Then, \dfrac{1}{t}=\dfrac{1}{\text{Time taken by Tim}}+\dfrac{1}{\text{Time taken by jim}}

\Rightarrow\ \dfrac{1}{t}=\dfrac{1}{10}+\dfrac{1}{15}\\\\\Rightarrow\ \dfrac{1}{t}=\dfrac{3+2}{30}=\dfrac{5}{30}\\\\\Rightarrow\dfrac{1}{t}=\dfrac{1}{6}\\\\\Rightarrow t=6

So, it will take<u> 6 hours</u> to complete the school project together .

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Answer:

The answer to your question is:   x = 7; y = 6

Step-by-step explanation:

                                             2x+y=20             ( 1 )  Multiply by 5

                                             6x−5y=12            ( 2 )

                               5 (2x+y=20)    = 10x + 5y = 100

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                                 14 + y = 20

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Answer:

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Data given and notation

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p_o=0.58 is the value that we want to test

\alpha=0.1 represent the significance level

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z would represent the statistic (variable of interest)

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