A shopkeeper packs 84 oranges and 126 mangoes into identical baskets. Each basket contains the same number of oranges and the same number of mangoes, with no fruit left over, and she wants to use the greatest possible number of baskets. (a) Find the greatest number of baskets she can use. (b) State how many oranges and how many mangoes are in each basket.

Type your working — one line per step, like you would write it on paper