Equation: f(x)=(1/5)x^2 or f(x)=(0.2)x^2
Check:
f(0)=(1/5)(0)^2
f(0)=(1/5)(0)
f(0)=0✓
f(5)=(1/5)(5)^2
f(5)=(1/5)(25)
f(5)=5✓
-3x+6.3=-14.4
-6.3=-6.3
-<u>3x</u>=-<u>20.7</u>
-3 -3
x=6.9
(2/5) of (2/3) of students = 4/15 of students study French. Then 1-(4/15) = 11/15 of students do not study French. The ratio you want is
(4/15):(11/15) = 4:11
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In a math expression "of" means "times".