On a voyage to atlantis, ariel from the little mermaid decided to pick up shells so that she could make necklaces for her mermaid friends. she picked up 30 green shells, 35 blue shells, and 30 yellow shells. 17 of the green shells had some blue in them. 15 of the shells had both yellow and blue in them, and 10 of the shells had both yellow and green in them. if just one shell had all three colors in it, how many total shells did ariel pick up?