Marbles - probability questions

[puzzle]

Ricky had a bag containing colorful marbles. The colors are red, green and blue. The total number of marbles he had in his bag is 60. There are 4 times as many red marbles as green marbles. 6 more blue marbles than green marbles. How many marbles of each color did Ricky have?

[murugan]

Lets take R as red, G as green and B as blue.
R + G + B = 60
As there are 4 times red marbles than green marbles, then
R = 4G
There are 6 more blue marbles than green marbles, so
B = G + 6
Therefore,
R + G + B = 60
4G + G + G + 6 = 60
6G + 6 = 60
6G = 60-6
6G = 54
G = 54/6 = 9
R = 4G = 4 x 9 = 36
B = G + 6 = 9 + 6 =15
Finally there are 9 green marbles, 36 red marbles and 15 blue marbles.