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.

In the final heat, the Mohammed family from Watford and the Smith family from Cumbria compete for the last remaining spot in the semi-finals.