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the numbers of marbles owned by Alex and Brian are in ratios 3:2.If Alex gives 80marbles to brian, the marbles owned by brian will be four times as many as tat owned by Alex.Suppose Alex has x marbles and Brian has y marbles originally 1.Set up 2 equations with x and y 2.find x and y

最佳解答:

1. x : y = 3 : 2, that is x/y = 3/2 or 2x = 3y................(1) 2. 4(x - 80) = y + 80...................(2) 4x - 320 = y + 80 4x - 400 = y. Sub. into (1) 2x = 3(4x - 400) 2x = 12x - 1200 10x = 1200 x = 120. y = 2x/3 = 240/3 = 80.

其他解答:

1 Let Alex has x marbles and Brian has y marbles Then x:y=3:2 or x/y=3/2 or 2x=3y Alex gives 80marbles to brian, the marbles owned by brian will be four times as many as tat owned by Alex 4(x-80)=y+80...(2) 2 substitute x=3y/2 into (2) 4(3y/2-80)=y+80 6y-320=y+80 5y=400 y=80 x=3*80/2=12063D0B758E2D502CC