Step-by-step explanation:
Let "c" be the original number of classrooms.
The 1200/c was the original number of students per classroom.
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Equation:
1200/(c-4) = (1200/c)+10
Multiply thru by c(c-4)
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1200c = 1200(c-4)+10c(c-4)
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1200c = 1200c-4800 + 10c^2-40c
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10c^2-40c-4800 = 0
c^2-4c-480 = 0
Factor:
(c-24)(c+20) = 0
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Positive solution:
c = 24 (# of classrooms originaly planned)
The answer is D) -3 Hope this help
Answer:
9.6 miles per hour
Step-by-step explanation:
First find the unit rate.
25/4= 0.16 miles per minute
Then multiply by 60 ( which we know theres 60 minutes in a hour.)
0.16x60=9.6
Answer:
320x^2+140x-10
Step-by-step explanation:
(16x-1)(20x+10)
320x^2+160x-20x-10
320x^2+140x-10
So simple... 3\ll=27\100 which equals 27.0 or 0.27