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3 years ago

95. A 20-gallon alcohol-water solution contains 15% pure alcohol. How much alcohol should

Mathematics

1 answer:

navik [9.2K]3 years ago

4 0

Answer:

1.25 gallons of alcohol

Step-by-step explanation:

Let x represent the amount of alcohol to add to the mix. Then the total amount of alcohol in the mix is ...

0.15×20 + x = 0.20×(20 +x)

3 +x = 4 + 0.2x . . . . simplify

0.8x = 1 . . . . . . . . . . add -3-0.2x

x = 1/0.8 = 1.25 . . . . divide by 0.8

1.25 gallons of alcohol should be added to make 21.25 gallons of 20% alcohol.

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Answer:

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Step-by-step explanation:

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Given,

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$r'_1(t)=(2,2t,4t^3)$

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The tangent at (0,0,0) is

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If θ is angle between tangent, then

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$\Rightarrow cos \theta =\frac{1}{\sqrt{30} }$

$\Rightarrow \theta =cos^{-1}\frac{1}{\sqrt{30} }$

$\Rightarrow \theta =79.48^\circ$

Therefore the angle of intersection is $\theta =79.48^\circ$ .

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