Final answer:
The question involves finding the percentage error with a measurement given to 1 significant figure for a 400 meter running track. Without knowing the exact range, it's assumed that the absolute error is ±50m, leading to a percentage error calculation of 12.5% based on a true value of 400m.
Step-by-step explanation:
The question is about determining the percentage error of the measured length of a running track that is 400 meters long, with the length measured to 1 significant figure. Since the length is given to one significant figure, the measurement could be anywhere between 350m and 450m, assuming the first significant figure is '4'. The percentage error of a measurement can be found using the absolute error over the true value times 100. However, without knowing the true value or the range within which the measurement was taken, we cannot calculate the percentage error exactly. It is common though to take the smallest unit of the significant figure as the absolute error, in this case, it would be ±50 meters. Therefore, for the sake of understanding how to calculate with an absolute error, if we take the absolute error as ±50m, then the percentage error using a true value of 400m would be (50/400)×100, which equals 12.5%.