There were 12 peaches on the tree originally. Let's make an equation to describe the problem and then solve it. "Bill picked 1/4 of the peaches on his grandmothers tree." Which means that 3/4ths of the original number of peaches remain. So: (3/4)x "After Bill finished Sally picked 1/3 of the peaches that were left on the tree." Which means that she left behind 2/3rds of the peaches that Bill left behind. So: (2/3)((3/4)x) "After Sally finished there were 6 peaches left on the tree." So: (2/3)((3/4)x) = 6 Now we just need to solve for x. (2/3)((3/4)x) = 6 (3/2) * (2/3)((3/4)x) = 6 * (3/2) (3/4)x = 9 (4/3)(3/4)x = 9*(4/3) x = 12 There were 12 peaches on the tree originally.