Sophie has a box of red, blue, and green marbles. There are 3 times as many red marbles as blue marbles, and 6 fewer green marbles than red marbles. If Sophie has 43 marbles in total, how many of each colour does she have?
Tom had some marbles. He gave half of them to Sarah. Then he gave one-third of the remaining marbles to James. After that, he had 20 marbles left. How many marbles did Tom have at the start?
Sophie has a box of sweets. She gives half of them to her friend Emma. Then she eats 6 sweets herself. After that, she gives a third of what’s left to her brother. Finally, she is left with 10 sweets. How many sweets did Sophie have at the start?