if you have 3 pounds of chocolate and scott eats one seventh sally eats four

[Pinky]

sevenths and charlie eats three? fifths how much chocolate is left

 

[peabody]

3 - 1/7 - 4/7 - 3/5
= 3 - 4/7 - 3/5
= 3 - 20/35 - 21/35
= 105/35 - 41/35
= 64/35
= 1 29/35