A 16-part series with Johnny Ball. Johnny bounces back with some lighthearted explorations into numbers and science.
This week Johnny gets thrown off balance by two junior judo champions, but realising the gravity of the situation, recovers sufficiently to take a bicycle ride on a tightrope. Does he fall off? Weight and see!
Meanwhile - weigh this one up.
A half is a third of it... what is it?
BBC Bristol
(Answer: one and a half)