The Lost Photo
Understand the puzzle
The exact puzzle
Zoe has 64 photos in one line, oldest to newest. Exactly one shows the first snow of winter, and Zoe knows that exact date. When she peeks at any photo, its date tells her whether the snow photo is EARLIER or LATER in the line (or she finds it). What is the smallest number of peeks that is ALWAYS enough to find the snow photo, even with the worst luck?
Why this matters
Use each test to eliminate as much as possible
Take your time reading. There's no rush at all. Use the picture on the side to help it make sense, then tell me what it's really asking.