What colour do you think these tennis balls are? - BBC News

Roger Federer weighs in on the debate as people are divided on whether tennis balls are yellow or green.

Why tennis balls are yellow is largely thanks to Sir David

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What colour is a tennis ball – green or yellow?

The reason tennis balls are yellow – or maybe green

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What color IS a tennis ball? Internet divided over yellow or green

Why do some people perceive a tennis ball, which is yellow by the

Tennis Balls Are Bright Yellow Thanks, in Part, to Sir David

Visually Impaired tennis

BBC to show Great Britain's Billie Jean King Cup Play-Off & Davis