Question 230978: In the US, the highest incidence of fraternal twins birth occurs among Asian-Americans, then African-Americans, then Caucasians. Of every 14600 births, the total number of fraternal twins births for all three is 701, where there are 176 more for Asian-Americans than African-Americans and 218 more for Asian-Americans than Caucasians. Determine the number for each race.
Out of every 14600 births, there are _____ sets of Asian-Americans twins, _____ sets of African-American twins, and _____ sets of Caucasian twins.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! In the US, the highest incidence of fraternal twins birth occurs among Asian-Americans, then African-Americans, then Caucasians. Of every 14600 births, the total number of fraternal twins births for all three is 701, where there are 176 more for Asian-Americans than African-Americans and 218 more for Asian-Americans than Caucasians. Determine the number for each race.
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As + Af + Ca = 701
As = Af +176
As = Ca + 218
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Substitute for Af and Ca to solve for As
Af = As-176
Ca = As-218
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As + (As-176) + (As-218) = 701
3As - 394 = 701
3As = 1095
As = 365 (# of Asian-American twin births)
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Since Af = As-176, Af = 365-176 = 189 (# of African-American twin births)
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Since Ca = As-218, Ca = 365-218 = 147 (# of Caucasian-American twin births)
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Cheers,
Stan H.
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