Question

daca y = 20% din x, z = 40% din x, x = 25% din t si x + y + z + t = 280, aflati x, y, z, t.

Answer 1

Răspuns:

x=50

y=10

z=20

t=200

Explicație pas cu pas:

y=(1/5)*x

z=(2/5)*x

x=(1/4)*t

x+y+z+t=280

Inlocuim in formula si  ajungem la : 25t+12x=5600

Inlocuim pe x => 28t=5600  => t= 200

Inlocuim si aflam x,y,z

x=(1/4)*200=50

y=(1/5)*50=10

z=(2/5)*50=20

Answer 2

Răspuns:

x=25/100 ×t echivalent cu x=1/4×t

y=20/100×x echivalent cu y=1/5×x=1/5×1/4×t=1/20×t

z=40/100×t echivalent cu z=2/5×x=2/5×1/4×t=2/20×t

Deci:

x+y+z+t=280 echivalent cu:

1/4×t+1/20×t+2/20×t+t=280(aducem la același numitor fractiile)

5/20×t+3/20×t+t=280

8/20×t+20/20×t=280

28/20×t=280(inmultim pe diagonala stiind ca 280=280/1)

t=200

x=1/4×t=200/4=50

y=1/20×t=200/20=100/10=10

z=2/20×t=200×2/20=400/20=200/10=20

Răspuns:x=50 y=10 z=20 t=200