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3 votes
In a bag, there are red and blue cubes in the ratio 4:7.

Sam adds 10 more red cubes to the bag.
Now there are red and blue cubes in the ratio 6:7.
How many blue cubes are in the bag?

User Qingchen
by
6.4k points

1 Answer

4 votes
x - red
y - blue


(x)/(y)=(4)/(7)\\ (x+10)/(y)=(6)/(7)\\\\ 7x=4y\\ 7x+70=6y\\ 4y+70=6y\\ 2y=70\\ y=35\\\\ 7x=4\cdot35\\ 7x=140\\ x=20
User RobinCominotto
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