In the second heat of the tournament, two more of Britain’s cleverest families go head to head to test their cerebral mettle. First up are the maths-crazy Smith family from Ayrshire - dad Chris, who was named Scottish Maths Teacher of the Year 2018, mum Elaine, a specialist teacher of the deaf, and their daughters Daisy, 12, who can quote pi to 20 decimal places, and Heidi, 11, who was the youngest person to win the Scottish Maths Challenge Award in 2018.

Their competition comes in the form of the Simmons family from Lewes, who hope their three generations of knowledge will be a recipe for success. Grandad Ricky, the eldest contestant at 80, is a retired print worker, and dad Jason is a graphic designer. They are joined by daughter and aspiring writer Jane, 15, and younger brother Robert, 11, who designs his own computer games.

Both teams push their brains to the limits to amass as much time as possible for the final round Interrogation. Can the Smith make the sum of their parts add up to victory, or will the Simmons use their collective experience to progress to the semi-final?

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