There are 100 balls in a bag. 0.25 of them are red balls, and the rest are green and blue balls. If there are 1/4 as many green balls as blue balls. How many blue balls are there?
25 are red
green + blue = 75
And there are 4 times as many green balls as blue
4B + B = 75
5B = 75
B = 75 /5 = 15 = blue ones
And the number of green ones = 60