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2 years ago

7

Three- eighths of the seventh grade students were taking advanced math at the beginning of the year,but seven dropped out by the

end of the year. If there were 140 students taking advanced math at the end of the year,how many total 7th grade students are there ?

1 answer:

vekshin12 years ago

7 0

392 because if there are 147 taking advanced math at the end of the year then 147 x 3/8 = 392

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By using <span>De Moivre's theorem:
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Part (C): find all of the fourth roots of this

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The second root = $z_{2} = 3 ( cos \ \frac{19\pi}{32} + i \ sin \ \frac{19\pi}{32})$

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The fourth root = $z_{4} = 3 ( cos \ \frac{51\pi}{32} + i \ sin \ \frac{51\pi}{32})$

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