The Boston Tea Party was an event during which crates of tea were thrown from ships into the river at the Boston harbor. This was done as a sign of protest against the British government and initiated the Independence war.
The “blank check” is an infamous episode in the history of the First World War; the first truly fatal error made by Germany – a promise of unconditional support for whatever action Austria-Hungary might take to punish Serbia.
An equivalent fraction to 5/40 would be 1/8