A la clase de matemáticas asistieron 140 estudiantes, si las niñas son la cuarta parte de los niños. ¿Cuántas niñas y cuántos niños hay en clase?

Because 3 = k/4 you can do any correct operation on both sides of an equation and it will still be equal. So you can multiply by 4.

k= 12 

y = 12/x and because x=2.

y = 12/2 = 6

So the answer is C.

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