John had a bag containing colourful marbles. The colours are red, green and blue. The total number of marbles he had in his bag was 60. There are 4 times as many red marbles as green marbles. 6 more blue marbles than green marbles. How many marbles of each colour did John have?
A chicken farmer has figured out that a hen and a half can lay an egg and a half in a day and a half. How many hens does the farmer need to produce one dozen eggs in six days?