Over the Rainbow with Googol and Googolplex

Googol and Googolplex are back from space, ready to continue their scavenger hunt. Pippa and Troy are eager to help, but runaway bulls and disappearing rainbows make their task difficult. And dangerous! Over the Rainbow with Googol and Googolplex is the third book in the Googol and Googolplex series. Book one is Down the Chimney with Googol and Googolplex. Book two is Under the Sea with Googol and Googolplex.