Rachel Riley has been temporarily replaced on Countdown by a tattooed YouTube mathematician who teaches equations in his underwear. Dr Tom Crawford, known for his Tom Rocks Maths channel on the ...

Rachel first joined Countdown in 2009, taking over from Carol Vorderman RACHEL Riley has been temporarily replaced on Countdown – by a YouTube star. The Channel 4 words and numbers show will undergo ...

Add Yahoo as a preferred source to see more of our stories on Google. (Channel 4) Countdown star Rachel Riley tried to contain her laughter on Tuesday’s episode after spelling out an X-rated phrase on ...

Countdown's Rachel Riley will be temporarily replaced by YouTube math star, Dr Tom Crawford. It was announced that Riley, Countdown's very own mathematician, will have to step down from her hosting ...

Rachel Riley has issued a playful warning to Countdown producers should they ever want her to leave the show. The 39-year-old mathematician is currently on a short break from the programme to focus on ...