kaylamayla2007
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Xavier, Yosef & Zeke are three brothers. All together they can do 56 push-ups in 3 minutes. Xavier does as many as Yosef and Zeke combined. Zeke does two less than half as many as Yosef does. How many push-ups does Yosef do?

A. 12
B. 28
C. 8
D. 6
E. 20​

Respuesta :

Yosef did 20 push-ups

Xavier(x), Yosef(y), Zeke(z).
x+y+z=56
y+z=x
(y/2)-2=z
we plug in for z to solve for y

y+(y/2)-2=x
Combine like terms
1.5y-2=x
Plug in for x and z in terms of y in the original problem

1.5y-2+y+.5y-2=56
Add like terms
3y-4=56
Add 4 from both sides
3y=60
Divide both sides by 3
y=20


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