Ryan has 40 balls. There are twice as many red balls as blue while the rest are green. If there are 11 blue balls, how many green balls are there?
##Solution## There are 11 blue x 2 red/blue = <<11*2=22>>22 red balls.
The total number of blue and red balls is 11 blue + 22 red = <<11+22=33>>33 balls
There are 40 balls - 33 balls = <<40-33=7>>7 green balls.
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