On one afternoon, Jo opens an umbrella just as a bell rings. Why is this alone not enough to show a correlation?

• One pair of events does not show a repeated pattern.
• The bell made the umbrella open.
• A correlation is possible only when one event causes another.

Across many days, two recorded quantities tend to rise together. What do we call this pattern?

• A cause
• A correlation
• An explanation

If two quantities are correlated, one must have caused the other.

A shop sells more umbrellas and more raincoats on rainy days. Which is a possible shared cause of the higher sales?

• Rain makes people want both items.
• Umbrella sales make the weather rainy.
• Raincoat sales make the weather rainy.

Players who stretch before practice tend to score more goals. Which question checks another factor before the coach claims stretching caused the difference?

• Which stretching move is the most fun to do?
• What colour shirts did the spectators wear?
• Do those players also spend more time practising?

In a made-up survey, children who eat breakfast tend to get higher grades. Which response to this pattern is justified?

• The link proves a cause.
• Another factor could help explain both.
• The survey rules out every other possible cause.

In a made-up survey, towns with more fire trucks tend to have more fires. Someone claims that trucks cause fires. Which possible explanation reverses that proposed causal direction?

• More fires may lead to more trucks.
• Town size may increase the counts of both fires and trucks.
• The two counts may form a pattern just by chance.

A student says, 'My team won every time I wore these socks, so the socks caused the wins.' What is missing from this reasoning?

• Proof that every player wore exactly the same socks.
• Proof that every winning team wears this kind of sock.
• Evidence for a cause beyond the socks-and-wins pattern.