Question 184467
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If 42% of the new school is african-american, then out of the 1000 students at the new school, 420 are african-american.


If <i>x</i> represents the number of students at one school and <i>y</i> represents the number of students at the second school.  We can establish three things:


1.  The sum of the students from the 2 schools must equal 1000:




(1) *[tex \Large \ \ \ \ \ \ \ \ \ \ \ \ x + y = 1000]



2. 90% of the first school is african-american, so you can say the number of african american students at school 1 is:



*[tex \Large \ \ \ \ \ \ \ \ \ \ \ \ 0.9x]


3. Likewise, the number of african american students at the second school is:


*[tex \Large \ \ \ \ \ \ \ \ \ \ \ \ 0.1y]


And we know that 420 is the sum of the african-americans at both schools, so:


(2) *[tex \Large \ \ \ \ \ \ \ \ \ \ \ \ 0.9x + 0.1y = 420]


Now (1) and (2) form a system of linear equations that can be solved by either substitution or elimination.


John
*[tex \Large e^{i \pi} + 1 = 0]
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